diff --git a/client/CLAUDE.md b/client/CLAUDE.md
index 32aeb884a..6e67e1af9 100644
--- a/client/CLAUDE.md
+++ b/client/CLAUDE.md
@@ -17,6 +17,7 @@ npm run lint:format       # Prettier: every .ts/.tsx/.mjs/.css file under src/,
 npm run lint:layers       # imports go downwards: components never import pages/ or mobile/, nothing under the views imports a view; per-file counts may only shrink (CI gate; --list, --update)
 npm run lint:offline      # no view file (components/mobile/pages/hooks) imports src/api/ beyond scripts/offline-baseline.json, which only shrinks (CI gate; --list, --update)
 npm run lint:skips        # no .only anywhere; skipped/todo/fixme tests per file may only shrink against scripts/skip-baseline.json (CI gate; skipIf/runIf and Playwright's test.skip(condition, 'why') are fine, but skipIf(true) and runIf(false) count as skips)
+npm run lint:i18n-keys    # every translation key src/ names exists in shared en (CI gate; --unused lists en keys nothing reaches)
 npm run test              # vitest run (tests/** + co-located src/**/*.test.{ts,tsx}); also test:unit / test:integration / test:coverage
 npm run e2e               # Playwright (CI runs --project=public --project=app; e2e:report opens the last report)
 npm run shots             # Playwright screenshot project (shots:promote to accept)
@@ -63,7 +64,7 @@ The offline core is flagship work surrounded by a periphery that ignores it. New
 ## Big-picture pieces
 
 - **Maps** (`src/components/Map/`): two interchangeable renderers — Leaflet and Mapbox/MapLibre GL — chosen at runtime by `MapViewAuto.tsx`. Keep both in sync when changing map features, and keep `mapbox-gl` and `maplibre-gl` in separate chunks (`check:gl-split`). The raster prefetcher fetches tiles `no-cors` so custom tile providers without CORS headers keep working; the vector prefetcher deliberately uses `cors` because it has to read the responses — don't "align" one with the other.
-- **i18n** (`src/i18n/TranslationContext.tsx`): `en` is bundled; every other locale is a dynamic `import('@trek/shared/i18n/<locale>')` so Vite emits one chunk per locale. Strings live in `shared/`, never here.
+- **i18n** (`src/i18n/TranslationContext.tsx`): `en` is bundled; every other locale is a dynamic `import('@trek/shared/i18n/<locale>')` so Vite emits one chunk per locale. Strings live in `shared/`, never here. `t()` returns an unknown key unchanged, so `lint:i18n-keys` (`scripts/i18n-keys.mjs`) resolves every literal key in `t()`, `tHtml()`, `tr()`, `<TransHtml html>`, `translateApiError` and `*Key` props against `shared/src/i18n/en`; a template key passes when its fixed parts match an en key, or through `DYNAMIC_ALLOWED` with a reason.
 - **Mobile shell** (`src/mobile/`): below the phone breakpoint (`useIsPhone`) `App.tsx` wraps routes in `MobileShell` and the `M*` screens under `mobile/screens/` take over. A UI change to a domain with an `M*` twin usually needs both — and the shared-hook rule below.
 - **Plugins UI** (`src/components/Plugins/`): third-party surfaces render only inside the sandboxed `PluginFrame` iframe (postMessage bridge, live theme-token sync). Host-rendered contribution points (widgets, schedule rows, map layers, planner columns/actions) render server-normalized primitives only — plugin markup never runs inline. Authoring is covered by the `trek-plugin-dev` skill.
 - **Managed installs** (`src/managed/index.tsx`): the attachment point for screens that only exist on a centrally administered install. Empty here by design — an operator replaces it at build time. Don't put features there.
diff --git a/client/package.json b/client/package.json
index 41266417c..f9ae1b0f2 100644
--- a/client/package.json
+++ b/client/package.json
@@ -25,6 +25,7 @@
     "lint:layers": "node scripts/layer-lint.mjs",
     "lint:offline": "node scripts/offline-lint.mjs",
     "lint:skips": "node scripts/skip-lint.mjs",
+    "lint:i18n-keys": "node scripts/i18n-keys.mjs",
     "check:gl-split": "node scripts/check-gl-split.mjs",
     "theme:lint": "node scripts/theme-lint.mjs",
     "theme:lint:strict": "node scripts/theme-lint.mjs --strict",
diff --git a/client/scripts/i18n-keys.mjs b/client/scripts/i18n-keys.mjs
new file mode 100644
index 000000000..a1bbfcfe1
--- /dev/null
+++ b/client/scripts/i18n-keys.mjs
@@ -0,0 +1,240 @@
+/*
+ * lint:i18n-keys: every translation key the client names exists in en.
+ *
+ * `t()` takes any string and returns the key itself when en has no such
+ * entry, so a typo or a key deleted from the locales renders as raw
+ * "budget.addCategory" text and nothing fails. Locale parity cannot see it:
+ * it compares the locales with en, not en with the code. This check reads
+ * src/ (tests aside) and resolves what it finds against shared/src/i18n/en:
+ *
+ *   t('x.y'), tHtml('x.y'), tr('x.y')   every string literal in the first
+ *                                       argument, so both sides of a
+ *                                       `cond ? 'a.b' : 'c.d'` are checked
+ *   <TransHtml html="x.y" />            the markup variant
+ *   translateApiError(t, err, 'x.y')    the fallback key
+ *   labelKey: 'x.y', titleKey="x.y"     any property or prop named *Key that
+ *                                       holds a dotted key, the tables
+ *                                       components feed to t() later
+ *   const guideKey = (id) => `help.${id}`  a key builder (help/registry.ts):
+ *                                       a template returned by a const
+ *                                       named *Key, read as a template key
+ *
+ * A key exists when en declares it, or declares `key.other` (a plural group
+ * whose general form is spelled out). A template literal key such as
+ * t(`budget.category.${id}`), or a prefix with the rest appended
+ * (t('costs.filter.' + f)), cannot be resolved; it passes when its fixed
+ * parts match at least one en key, and otherwise only through DYNAMIC_ALLOWED.
+ * A key held in a variable (`t(opt.label)`) is out of reach unless the table
+ * names it in a *Key property.
+ *
+ *   npm run lint:i18n-keys              check (CI)
+ *   npm run lint:i18n-keys -- --unused  also list en keys no literal or pattern reaches
+ *
+ * The unused list is information, not a gate: keys reached through a
+ * variable (`t(item.labelKey)` with the table elsewhere, server-sent error
+ * keys) look unused here.
+ */
+import { existsSync, readdirSync, readFileSync, realpathSync, statSync } from 'node:fs'
+import { dirname, join, relative } from 'node:path'
+import { fileURLToPath, pathToFileURL } from 'node:url'
+
+// Plain paths rather than `new URL(..., import.meta.url)`: under the test runner's DOM environment URL is
+// jsdom's, which fileURLToPath refuses.
+const HERE = dirname(fileURLToPath(import.meta.url))
+const SRC = join(HERE, '..', 'src')
+const SHARED_SCRIPTS = join(HERE, '..', '..', 'shared', 'scripts')
+
+/**
+ * Template literal keys whose fixed parts match no en key, each with the
+ * reason it still resolves and the keys it resolves to, which must exist.
+ * Keep this short: every entry is a key the check cannot follow.
+ */
+export const DYNAMIC_ALLOWED = [
+  {
+    template: '${opt.label}Hint',
+    because:
+      'TripShareDialog appends Hint to each SHARE_OPTIONS label (useTripShare.ts); share.optTravelOnlyHint ' +
+      'and share.optHideImagesHint exist, and the template has no fixed part to match them by',
+    resolves: ['share.optTravelOnlyHint', 'share.optHideImagesHint'],
+  },
+]
+
+const KEY_RE = /^[a-z][a-zA-Z0-9_]*(?:\.[a-zA-Z0-9_:-]+)+$/
+const PREFIX_RE = /^[a-z][a-zA-Z0-9_]*(?:\.[a-zA-Z0-9_:-]+)*\.$/
+const CALL_RE = /(?<![\w$.])(?:t|tHtml|tr)\(|(?<=[\w$]\.)(?:t|tHtml)\(/g
+const HTML_PROP_RE = /<TransHtml\b[^>]*?\bhtml=(["'])([^"'\n]+)\1/g
+const API_ERROR_RE = /\btranslateApiError\(\s*t\s*,[^,()]*(?:\([^()]*\))?[^,()]*,\s*(['"])([^'"\n]+)\1/g
+const KEY_BUILDER_RE = /\bconst\s+[a-zA-Z]*Key\s*=\s*\([^)]*\)\s*(?::\s*[^=]+?)?=>\s*`((?:\\.|\$\{[^}]*\}|[^`\\])*)`/g
+const KEY_PROP_RE = /\b[a-zA-Z]*Key\s*(?::|=\{?)\s*(['"])([a-z][a-zA-Z0-9_]*\.[^'"\s]+)\1/g
+
+function walk(dir, files = []) {
+  for (const name of readdirSync(dir)) {
+    const path = join(dir, name)
+    if (statSync(path).isDirectory()) walk(path, files)
+    else if (/\.tsx?$/.test(name) && !/\.(?:test|spec)\./.test(name) && !name.endsWith('.d.ts')) files.push(path)
+  }
+  return files
+}
+
+const lineAt = (text, index) => text.slice(0, index).split('\n').length
+
+/**
+ * The source of the first argument of the call whose `(` sits at `open`:
+ * everything up to the top-level comma or the closing parenthesis, with
+ * strings, template literals and nested brackets skipped as units.
+ */
+export function firstArgument(text, open) {
+  let depth = 0
+  for (let i = open + 1; i < text.length; i++) {
+    const c = text[i]
+    if (c === "'" || c === '"' || c === '`') {
+      for (i++; i < text.length && text[i] !== c; i++) {
+        if (text[i] === '\\') i++
+        else if (c === '`' && text[i] === '$' && text[i + 1] === '{') {
+          // Skip the interpolation, counting its braces.
+          let braces = 0
+          for (; i < text.length; i++) {
+            if (text[i] === '{') braces++
+            else if (text[i] === '}' && --braces === 0) break
+          }
+        }
+      }
+      continue
+    }
+    if (c === '(' || c === '[' || c === '{') depth++
+    else if (c === ')' || c === ']' || c === '}') {
+      if (depth === 0) return text.slice(open + 1, i)
+      depth--
+    } else if (c === ',' && depth === 0) return text.slice(open + 1, i)
+  }
+  return text.slice(open + 1)
+}
+
+/** The quoted literals and template literals of an argument's source. */
+export function literalsIn(arg) {
+  const quoted = []
+  const templates = []
+  for (const m of arg.matchAll(/(['"])((?:\\.|(?!\1)[^\\\n])*)\1|`((?:\\.|\$\{[^}]*\}|[^`\\])*)`/g)) {
+    if (m[3] !== undefined) templates.push(m[3])
+    else quoted.push(m[2])
+  }
+  return { quoted, templates }
+}
+
+/** A template literal's key pattern: its fixed parts, anything in between. Null when it has no fixed dotted prefix. */
+export function templatePattern(template) {
+  const parts = template.split(/\$\{[^}]*\}/)
+  if (!/^[a-z][a-zA-Z0-9_]*\./.test(parts[0] ?? '')) return null
+  const escape = (s) => s.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
+  return new RegExp(`^${parts.map(escape).join('.+')}$`)
+}
+
+/** Every key reference in one file's source. */
+export function scanSource(text, file = '<source>') {
+  const literal = []
+  const dynamic = []
+  for (const m of text.matchAll(CALL_RE)) {
+    const open = m.index + m[0].length - 1
+    const { quoted, templates } = literalsIn(firstArgument(text, open))
+    const line = lineAt(text, m.index)
+    for (const key of quoted) {
+      if (KEY_RE.test(key)) literal.push({ file, line, key })
+      // t('costs.filter.' + f): a prefix with the rest appended, read like a template.
+      else if (PREFIX_RE.test(key)) dynamic.push({ file, line, template: `${key}\${…}`, pattern: templatePattern(`${key}\${…}`) })
+    }
+    for (const template of templates) {
+      if (!template.includes('${')) {
+        if (KEY_RE.test(template)) literal.push({ file, line, key: template })
+        continue
+      }
+      dynamic.push({ file, line, template, pattern: templatePattern(template) })
+    }
+  }
+  for (const m of text.matchAll(KEY_BUILDER_RE)) {
+    // Builders of other strings (cache keys) have no fixed dotted prefix and are not translation keys.
+    const pattern = templatePattern(m[1])
+    if (pattern) dynamic.push({ file, line: lineAt(text, m.index), template: m[1], pattern })
+  }
+  for (const re of [HTML_PROP_RE, API_ERROR_RE, KEY_PROP_RE]) {
+    for (const m of text.matchAll(re)) {
+      if (KEY_RE.test(m[2])) literal.push({ file, line: lineAt(text, m.index), key: m[2] })
+    }
+  }
+  return { literal, dynamic }
+}
+
+/** en's keys, read from the locale sources with the shared parity tooling's reader. */
+export async function readEnKeys() {
+  const { listDomainFiles, readCatalog } = await import(pathToFileURL(join(SHARED_SCRIPTS, 'i18n-catalog.mjs')).href)
+  const keys = new Set()
+  for (const file of listDomainFiles('en')) for (const { key } of readCatalog('en', file)) keys.add(key)
+  if (keys.size === 0) throw new Error('shared/src/i18n/en holds no keys: the reader or the path is broken')
+  return keys
+}
+
+export const hasKey = (enKeys, key) => enKeys.has(key) || enKeys.has(`${key}.other`)
+
+/**
+ * The verdict over a scan: literal keys en lacks, template keys no en key
+ * matches (unless allowed), allow-list entries nothing uses any more, and
+ * the en keys nothing reaches.
+ */
+export function evaluate(scan, enKeys, allowed = DYNAMIC_ALLOWED) {
+  const missing = scan.literal.filter(({ key }) => !hasKey(enKeys, key))
+  const allowedTemplates = new Set(allowed.map((a) => a.template))
+  const unmatched = scan.dynamic.filter(
+    ({ template, pattern }) =>
+      !allowedTemplates.has(template) && !(pattern && [...enKeys].some((k) => pattern.test(k))),
+  )
+  const usedTemplates = new Set(scan.dynamic.map((d) => d.template))
+  const stale = allowed.filter((a) => !usedTemplates.has(a.template) || a.resolves.some((k) => !hasKey(enKeys, k)))
+  const reached = new Set([...scan.literal.map((l) => l.key), ...allowed.flatMap((a) => a.resolves)])
+  const patterns = scan.dynamic.map((d) => d.pattern).filter(Boolean)
+  const base = (k) => k.replace(/\.(?:zero|one|two|few|many|other)$/, '')
+  const unused = [...enKeys].filter(
+    (k) => !reached.has(k) && !reached.has(base(k)) && !patterns.some((p) => p.test(k) || p.test(base(k))),
+  )
+  return { missing, unmatched, stale, unused }
+}
+
+export function scanTree(root = SRC) {
+  if (!existsSync(root)) throw new Error(`${root} does not exist`)
+  const scan = { literal: [], dynamic: [] }
+  for (const path of walk(root)) {
+    const found = scanSource(readFileSync(path, 'utf8'), relative(root, path).split('\\').join('/'))
+    scan.literal.push(...found.literal)
+    scan.dynamic.push(...found.dynamic)
+  }
+  if (scan.literal.length === 0) throw new Error(`no translation key found under ${root}: the scanner is broken`)
+  return scan
+}
+
+// Compared by real path, so the check still runs when the script is started through a symlink.
+const isCli =
+  Boolean(process.argv[1]) && existsSync(process.argv[1]) && realpathSync(process.argv[1]) === fileURLToPath(import.meta.url)
+if (isCli) {
+  try {
+    const scan = scanTree()
+    const enKeys = await readEnKeys()
+    const { missing, unmatched, stale, unused } = evaluate(scan, enKeys)
+    for (const { file, line, key } of missing) {
+      console.error(`FAIL  ${file}:${line}: '${key}' is not a key in shared/src/i18n/en`)
+    }
+    for (const { file, line, template } of unmatched) {
+      console.error(`FAIL  ${file}:${line}: \`${template}\` matches no key in shared/src/i18n/en`)
+    }
+    for (const { template } of stale) {
+      console.error(`FAIL  DYNAMIC_ALLOWED lists \`${template}\`, which no file uses any more: remove the entry`)
+    }
+    if (process.argv.includes('--unused')) for (const key of unused.sort()) console.log(`unused  ${key}`)
+    console.log(
+      `i18n keys: ${new Set(scan.literal.map((l) => l.key)).size} literal and ${scan.dynamic.length} template ` +
+        `reference(s) checked against ${enKeys.size} en keys; ${unused.length} en key(s) reached by neither ` +
+        '(information, --unused lists them)',
+    )
+    if (missing.length || unmatched.length || stale.length) process.exit(1)
+  } catch (err) {
+    console.error(`FAIL  ${err.message}`)
+    process.exit(1)
+  }
+}
diff --git a/client/tests/unit/i18n/i18nKeysScript.test.ts b/client/tests/unit/i18n/i18nKeysScript.test.ts
new file mode 100644
index 000000000..b240d3180
--- /dev/null
+++ b/client/tests/unit/i18n/i18nKeysScript.test.ts
@@ -0,0 +1,109 @@
+import { mkdtempSync, rmSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { describe, expect, it } from 'vitest'
+import {
+  DYNAMIC_ALLOWED,
+  evaluate,
+  firstArgument,
+  readEnKeys,
+  scanSource,
+  scanTree,
+  templatePattern,
+} from '../../../scripts/i18n-keys.mjs'
+
+// FE-I18N-KEYS-001 to FE-I18N-KEYS-010: the client key check (scripts/i18n-keys.mjs).
+
+const EN = new Set(['budget.title', 'places.count', 'places.count.one', 'trips.total.other', 'trips.total.one', 'costs.filter.all'])
+
+describe('i18n key check', () => {
+  it('FE-I18N-KEYS-001: finds literal keys in t, tHtml, tr, TransHtml, translateApiError and *Key props', () => {
+    const { literal } = scanSource([
+      "t('budget.title')",
+      'props.t("places.count", { count })',
+      "tHtml('a.html')",
+      "tr('pdf.mapTitle')",
+      '<TransHtml html="journey.text" />',
+      "translateApiError(t, err, 'files.uploadError')",
+      "const tabs = [{ labelKey: 'tabs.one' }]",
+      '<Hint titleKey="hint.title" />',
+    ].join('\n'))
+    expect(literal.map((l) => l.key)).toEqual([
+      'budget.title', 'places.count', 'a.html', 'pdf.mapTitle', 'journey.text', 'files.uploadError', 'tabs.one', 'hint.title',
+    ])
+  })
+
+  it('FE-I18N-KEYS-002: checks both sides of a conditional key and ignores later arguments', () => {
+    const { literal } = scanSource("t(open ? 'a.open' : 'a.closed', { name: 'x.y' })")
+    expect(literal.map((l) => l.key)).toEqual(['a.open', 'a.closed'])
+    expect(firstArgument("t(fn(a, b) ? 'x.y' : 'z.w', 1)", 1)).toBe("fn(a, b) ? 'x.y' : 'z.w'")
+  })
+
+  it('FE-I18N-KEYS-003: reads templates, appended prefixes and key builders as patterns', () => {
+    const { literal, dynamic } = scanSource([
+      't(`costs.filter.${f}`)',
+      "t('costs.filter.' + f)",
+      't(`plain.key`)',
+      'export const guideKey = (id: string): string =>\n  `help.guide.${id}.title`',
+      'const cacheKey = (id: number): string => `${id} x`',
+      "const other = notATranslation('x.y')",
+    ].join('\n'))
+    expect(literal.map((l) => l.key)).toEqual(['plain.key'])
+    expect(dynamic.map((d) => d.template)).toEqual(['costs.filter.${f}', 'costs.filter.${…}', 'help.guide.${id}.title'])
+    expect(templatePattern('costs.filter.${f}')!.test('costs.filter.all')).toBe(true)
+    expect(templatePattern('${opt.label}Hint')).toBeNull()
+  })
+
+  it('FE-I18N-KEYS-004: fails a literal key en lacks and accepts a plural group by its general form', () => {
+    const scan = scanSource("t('budget.addCategory'); t('places.count', { count }); t('trips.total', { count })")
+    const { missing } = evaluate(scan, EN, [])
+    expect(missing.map((m) => m.key)).toEqual(['budget.addCategory'])
+  })
+
+  it('FE-I18N-KEYS-005: fails a template no en key matches unless it is allowed with the keys it resolves to', () => {
+    const scan = scanSource('t(`costs.filter.${f}`); t(`gone.prefix.${x}`); t(`${opt.label}Hint`)')
+    expect(evaluate(scan, EN, []).unmatched.map((u) => u.template)).toEqual(['gone.prefix.${x}', '${opt.label}Hint'])
+    const allowed = [{ template: '${opt.label}Hint', because: 'test', resolves: ['budget.title'] }]
+    const result = evaluate(scan, EN, allowed)
+    expect(result.unmatched.map((u) => u.template)).toEqual(['gone.prefix.${x}'])
+    expect(result.stale).toEqual([])
+  })
+
+  it('FE-I18N-KEYS-006: refuses an allow-list entry nothing uses or whose keys en lacks', () => {
+    const scan = scanSource('t(`${opt.label}Hint`)')
+    const unused = [{ template: '${gone}', because: 'test', resolves: ['budget.title'] }]
+    expect(evaluate(scan, EN, unused).stale).toEqual(unused)
+    const wrong = [{ template: '${opt.label}Hint', because: 'test', resolves: ['share.nope'] }]
+    expect(evaluate(scan, EN, wrong).stale).toEqual(wrong)
+  })
+
+  it('FE-I18N-KEYS-007: reports en keys neither a literal nor a pattern reaches', () => {
+    const scan = scanSource("t('budget.title'); t('places.count', { count }); t(`costs.filter.${f}`)")
+    expect(evaluate(scan, EN, []).unused).toEqual(['trips.total.other', 'trips.total.one'])
+  })
+
+  it('FE-I18N-KEYS-008: every allow-list entry carries a reason and the keys it resolves to', () => {
+    for (const entry of DYNAMIC_ALLOWED) {
+      expect(entry.because.length).toBeGreaterThan(20)
+      expect(entry.resolves.length).toBeGreaterThan(0)
+    }
+  })
+
+  it('FE-I18N-KEYS-009: fails closed on a missing source tree or one without any key', () => {
+    expect(() => scanTree(join(tmpdir(), 'trek-i18n-keys-does-not-exist'))).toThrow(/does not exist/)
+    const empty = mkdtempSync(join(tmpdir(), 'trek-i18n-keys-'))
+    try {
+      expect(() => scanTree(empty)).toThrow(/scanner is broken/)
+    } finally {
+      rmSync(empty, { recursive: true, force: true })
+    }
+  })
+
+  it('FE-I18N-KEYS-010: the client source names no key en lacks today', async () => {
+    const enKeys = await readEnKeys()
+    const { missing, unmatched, stale } = evaluate(scanTree(), enKeys)
+    expect(missing).toEqual([])
+    expect(unmatched).toEqual([])
+    expect(stale).toEqual([])
+  })
+})
diff --git a/shared/CLAUDE.md b/shared/CLAUDE.md
index 300a0605b..df8ad7dd7 100644
--- a/shared/CLAUDE.md
+++ b/shared/CLAUDE.md
@@ -50,6 +50,7 @@ The parity rule governs **existing** routes; it is not a license to mint new deb
 - **Every locale gets a real translation — an English placeholder is not acceptable.** Parity only checks that the key exists, so copying the `en` string passes CI while shipping English to those users. Write native phrasing with the locale's own punctuation and the same `{placeholders}` as `en`; if you genuinely cannot translate one, say so instead of filling it with English.
 - **Count-bearing strings use plural forms, never `count === 1` in the caller.** The key holds the general form (the CLDR "other" category) and `key.zero|one|two|few|many` hold the forms the language's `Intl.PluralRules` selects for whole numbers (`plural.ts`); `t(key, { count })` (or `{ n }`) picks one. Pass the count as a number. Russian needs `.one`, `.few` and `.many`, Arabic all five, Japanese none. `i18n:parity` checks that every locale has exactly the forms its language reaches with whole numbers and none it never selects. A form may spell the number out (Arabic "ملف واحد") only where its category is that one number; French `one` also covers 0 and Russian `one` covers 21, so they keep `{count}`.
 - **Further i18n specs run in `npm test`** and fail changes that parity lets through: placeholder parity (every `{placeholder}` in an `en` string must appear in each translation), no `en` string may call TREK "self-hosted" (the same build runs on managed installs; exemptions live in the spec), and a wording regression test for plugin permission descriptions (currently one string — add a case there when a permission's real behavior changes). None of these are part of `i18n:parity`, which checks key sets and plural forms only.
+- **en holds every key the client names.** `npm run lint:i18n-keys` in `client/` resolves the keys `src/` passes to `t()` and its helpers against `en/`, read through `scripts/i18n-catalog.mjs`. That reader takes the tables as text: a value must be one string literal on the key's line or the next, and anything else (a concatenation, a template literal) is an error rather than a skipped key. Its spec uses the fixtures in `scripts/fixtures/`.
 
 ## Sanitization (`src/sanitize/sanitize.ts`)
 
diff --git a/shared/scripts/fixtures/i18n/de/a.ts b/shared/scripts/fixtures/i18n/de/a.ts
new file mode 100644
index 000000000..161ef0d78
--- /dev/null
+++ b/shared/scripts/fixtures/i18n/de/a.ts
@@ -0,0 +1,14 @@
+// Fixture: two unmarked English copies (a.title, a.multi), one marked (a.lone).
+const a = {
+  'a.title': 'Trip settings',
+  'a.count': '{count} Orte',
+  'a.count.one': '{count} Ort',
+  'a.lone': 'Remove {count} items', // en-fallback
+  'a.day': 'Tag {n}',
+  'a.brand': 'Google Maps',
+  'a.code': 'GPX',
+  'a.quote': 'Es ist hier',
+  'a.multi':
+    'A long sentence that wraps onto the next line',
+};
+export default a;
diff --git a/shared/scripts/fixtures/i18n/en/a.ts b/shared/scripts/fixtures/i18n/en/a.ts
new file mode 100644
index 000000000..83affa1e6
--- /dev/null
+++ b/shared/scripts/fixtures/i18n/en/a.ts
@@ -0,0 +1,14 @@
+// Fixture for the i18n script specs: a canonical table.
+const a = {
+  'a.title': 'Trip settings',
+  'a.count': '{count} places',
+  'a.count.one': '{count} place',
+  'a.lone': 'Remove {count} items',
+  'a.day': 'Day {n}',
+  'a.brand': 'Google Maps',
+  'a.code': 'GPX',
+  'a.quote': "It's here",
+  'a.multi':
+    'A long sentence that wraps onto the next line',
+};
+export default a;
diff --git a/shared/scripts/i18n-catalog.mjs b/shared/scripts/i18n-catalog.mjs
new file mode 100644
index 000000000..bcb2a035c
--- /dev/null
+++ b/shared/scripts/i18n-catalog.mjs
@@ -0,0 +1,103 @@
+/**
+ * Reads the locale tables as text, for the i18n scripts beside this file.
+ *
+ * Plain .mjs outside `src/` for the reason i18n-parity.mjs gives: shared's
+ * typecheck runs without @types/node, and the CI parity job runs these scripts
+ * with no install at all. The tables are parsed rather than imported so the
+ * checks stay synchronous and see the `// en-fallback` markers, which an
+ * import would strip.
+ *
+ * A value is one string literal, single or double quoted, on the key's line or
+ * the next one (the two shapes Prettier writes). Anything else after a key (a
+ * concatenation, a template literal, a call) is an error rather than a skipped
+ * key: a check that silently reads less than the file holds passes for the
+ * wrong reason.
+ */
+import { readdirSync, readFileSync, statSync } from 'node:fs';
+import { dirname, join } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+export const I18N_ROOT = join(dirname(fileURLToPath(import.meta.url)), '..', 'src', 'i18n');
+
+export const FALLBACK_MARKER = '// en-fallback';
+
+/** A root given as a file URL (what a spec can build without node types) or a path. */
+export const asPath = (root) => (root instanceof URL ? fileURLToPath(root) : root);
+
+/** Every locale folder (externalNotifications is a barrel module, not a locale). */
+export function listLocales(root = I18N_ROOT) {
+  const dir = asPath(root);
+  return readdirSync(dir)
+    .filter((name) => statSync(join(dir, name)).isDirectory())
+    .filter((name) => name !== 'externalNotifications');
+}
+
+/** The domain files of one locale, sorted. */
+export function listDomainFiles(locale, root = I18N_ROOT) {
+  return readdirSync(join(asPath(root), locale))
+    .filter((f) => f.endsWith('.ts') && f !== 'index.ts')
+    .sort();
+}
+
+const KEY_LINE_RE = /^\s*'([a-z][a-zA-Z0-9.\-_:]*)'\s*:(.*)$/;
+
+const ESCAPES = { n: '\n', r: '\r', t: '\t', b: '\b', f: '\f', v: '\v', 0: '\0' };
+
+/** The value of a JS string literal body (between the quotes). */
+export function decodeLiteral(body) {
+  return body.replace(/\\(u\{[0-9a-fA-F]+\}|u[0-9a-fA-F]{4}|x[0-9a-fA-F]{2}|\r?\n|[\s\S])/g, (_, esc) => {
+    if (esc[0] === 'u' && esc.length > 1) return String.fromCodePoint(parseInt(esc.replace(/[u{}]/g, ''), 16));
+    if (esc[0] === 'x' && esc.length === 3) return String.fromCharCode(parseInt(esc.slice(1), 16));
+    if (esc === '\n' || esc === '\r\n') return '';
+    return ESCAPES[esc] ?? esc;
+  });
+}
+
+/** Reads one quoted literal at the start of `text`; null when `text` does not start with one. */
+function readLiteral(text) {
+  const quote = text[0];
+  if (quote !== "'" && quote !== '"') return null;
+  for (let i = 1; i < text.length; i++) {
+    if (text[i] === '\\') {
+      i++;
+      continue;
+    }
+    if (text[i] === '\n') return null;
+    if (text[i] === quote) return { value: decodeLiteral(text.slice(1, i)), rest: text.slice(i + 1) };
+  }
+  return null;
+}
+
+/**
+ * Every top-level entry of one table's source: key, value, whether the
+ * declaration carries the fallback marker, and the line it starts on.
+ * Throws with file and line on anything it cannot read.
+ */
+export function parseCatalog(source, label = 'catalogue') {
+  const lines = source.replace(/\r\n?/g, '\n').split('\n');
+  const entries = [];
+  for (let i = 0; i < lines.length; i++) {
+    const match = lines[i].match(KEY_LINE_RE);
+    if (!match) continue;
+    const [, key, after] = match;
+    let text = after.trim();
+    let end = i;
+    if (text === '') {
+      end = i + 1;
+      text = (lines[end] ?? '').trim();
+    }
+    const literal = readLiteral(text);
+    const tail = literal?.rest.trim() ?? '';
+    if (!literal || !/^(,|\})?\s*(\/\/.*)?$/.test(tail)) {
+      throw new Error(`${label}:${i + 1}: '${key}' is not a single string literal`);
+    }
+    entries.push({ key, value: literal.value, marked: tail.includes(FALLBACK_MARKER), line: i + 1 });
+    i = end;
+  }
+  return entries;
+}
+
+/** The entries of `locale/file`, read from disk. */
+export function readCatalog(locale, file, root = I18N_ROOT) {
+  return parseCatalog(readFileSync(join(asPath(root), locale, file), 'utf8'), `${locale}/${file}`);
+}
diff --git a/shared/src/i18n/ar/budget.ts b/shared/src/i18n/ar/budget.ts
index 6b4843b07..9dda87cfe 100644
--- a/shared/src/i18n/ar/budget.ts
+++ b/shared/src/i18n/ar/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'إنشاء فئة',
   'budget.category': 'الفئة',
   'budget.categoryName': 'اسم الفئة',
+  'budget.addCategory': 'إضافة فئة',
   'budget.table.name': 'الاسم',
   'budget.table.total': 'الإجمالي',
   'budget.table.persons': 'الأشخاص',
diff --git a/shared/src/i18n/ar/common.ts b/shared/src/i18n/ar/common.ts
index a0437246b..0f57ab6d3 100644
--- a/shared/src/i18n/ar/common.ts
+++ b/shared/src/i18n/ar/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'إلغاء',
   'common.clear': 'مسح',
   'common.delete': 'حذف',
+  'common.remove': 'إزالة',
   'common.preview': 'معاينة',
   'common.edit': 'تعديل',
   'common.add': 'إضافة',
diff --git a/shared/src/i18n/az/budget.ts b/shared/src/i18n/az/budget.ts
index af9712794..40cb34705 100644
--- a/shared/src/i18n/az/budget.ts
+++ b/shared/src/i18n/az/budget.ts
@@ -12,6 +12,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Kateqoriya yarat',
   'budget.category': 'Kateqoriya',
   'budget.categoryName': 'Kateqoriyanın adı',
+  'budget.addCategory': 'Kateqoriya əlavə et',
 
   'budget.table.name': 'Ad',
   'budget.table.total': 'Ümumi',
diff --git a/shared/src/i18n/az/common.ts b/shared/src/i18n/az/common.ts
index 8c4b1f9ec..ba3dcdf44 100644
--- a/shared/src/i18n/az/common.ts
+++ b/shared/src/i18n/az/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Ləğv et',
   'common.clear': 'Təmizlə',
   'common.delete': 'Sil',
+  'common.remove': 'Sil',
   'common.preview': 'Önizləmə',
   'common.edit': 'Redaktə et',
   'common.add': 'Əlavə et',
diff --git a/shared/src/i18n/br/budget.ts b/shared/src/i18n/br/budget.ts
index 7f900deb1..8fc24cc45 100644
--- a/shared/src/i18n/br/budget.ts
+++ b/shared/src/i18n/br/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Criar categoria',
   'budget.category': 'Categoria',
   'budget.categoryName': 'Nome da categoria',
+  'budget.addCategory': 'Adicionar categoria',
   'budget.table.name': 'Nome',
   'budget.table.total': 'Total',
   'budget.table.persons': 'Pessoas',
diff --git a/shared/src/i18n/br/common.ts b/shared/src/i18n/br/common.ts
index a81b0b76f..d8e3eb391 100644
--- a/shared/src/i18n/br/common.ts
+++ b/shared/src/i18n/br/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Cancelar',
   'common.clear': 'Limpar',
   'common.delete': 'Excluir',
+  'common.remove': 'Remover',
   'common.preview': 'Prévia',
   'common.edit': 'Editar',
   'common.add': 'Adicionar',
diff --git a/shared/src/i18n/ca/budget.ts b/shared/src/i18n/ca/budget.ts
index d9dc8d887..39655f0a3 100644
--- a/shared/src/i18n/ca/budget.ts
+++ b/shared/src/i18n/ca/budget.ts
@@ -9,6 +9,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Crea una categoria',
   'budget.category': 'Categoria',
   'budget.categoryName': 'Nom de la categoria',
+  'budget.addCategory': 'Afegeix una categoria',
   'budget.table.name': 'Nom',
   'budget.table.total': 'Total',
   'budget.table.persons': 'Persones',
diff --git a/shared/src/i18n/ca/common.ts b/shared/src/i18n/ca/common.ts
index dab02cd50..acfcf430c 100644
--- a/shared/src/i18n/ca/common.ts
+++ b/shared/src/i18n/ca/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Cancel·lar',
   'common.clear': 'Esborrar',
   'common.delete': 'Eliminar',
+  'common.remove': 'Elimina',
   'common.preview': 'Vista prèvia',
   'common.edit': 'Editar',
   'common.add': 'Afegir',
diff --git a/shared/src/i18n/cs/budget.ts b/shared/src/i18n/cs/budget.ts
index 77b87fb55..b7de4453d 100644
--- a/shared/src/i18n/cs/budget.ts
+++ b/shared/src/i18n/cs/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Vytvořit kategorii',
   'budget.category': 'Kategorie',
   'budget.categoryName': 'Název kategorie',
+  'budget.addCategory': 'Přidat kategorii',
   'budget.table.name': 'Název',
   'budget.table.total': 'Celkem',
   'budget.table.persons': 'Osoby',
diff --git a/shared/src/i18n/cs/common.ts b/shared/src/i18n/cs/common.ts
index 9f692890a..07d4fe8bf 100644
--- a/shared/src/i18n/cs/common.ts
+++ b/shared/src/i18n/cs/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Zrušit',
   'common.clear': 'Vymazat',
   'common.delete': 'Smazat',
+  'common.remove': 'Odstranit',
   'common.preview': 'Náhled',
   'common.edit': 'Upravit',
   'common.add': 'Přidat',
diff --git a/shared/src/i18n/de/budget.ts b/shared/src/i18n/de/budget.ts
index f0643a486..fd71b1cef 100644
--- a/shared/src/i18n/de/budget.ts
+++ b/shared/src/i18n/de/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Kategorie erstellen',
   'budget.category': 'Kategorie',
   'budget.categoryName': 'Kategoriename',
+  'budget.addCategory': 'Kategorie hinzufügen',
   'budget.table.name': 'Name',
   'budget.table.total': 'Gesamt',
   'budget.table.persons': 'Personen',
diff --git a/shared/src/i18n/de/common.ts b/shared/src/i18n/de/common.ts
index f9d35366d..1db340ba2 100644
--- a/shared/src/i18n/de/common.ts
+++ b/shared/src/i18n/de/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Abbrechen',
   'common.clear': 'Löschen',
   'common.delete': 'Löschen',
+  'common.remove': 'Entfernen',
   'common.preview': 'Vorschau',
   'common.edit': 'Bearbeiten',
   'common.add': 'Hinzufügen',
diff --git a/shared/src/i18n/en/budget.ts b/shared/src/i18n/en/budget.ts
index c7deeed8f..9f23b3179 100644
--- a/shared/src/i18n/en/budget.ts
+++ b/shared/src/i18n/en/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Create Category',
   'budget.category': 'Category',
   'budget.categoryName': 'Category Name',
+  'budget.addCategory': 'Add category',
   'budget.table.name': 'Name',
   'budget.table.total': 'Total',
   'budget.table.persons': 'Persons',
diff --git a/shared/src/i18n/en/common.ts b/shared/src/i18n/en/common.ts
index 23d1c6aad..004fa17ff 100644
--- a/shared/src/i18n/en/common.ts
+++ b/shared/src/i18n/en/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Cancel',
   'common.clear': 'Clear',
   'common.delete': 'Delete',
+  'common.remove': 'Remove',
   'common.preview': 'Preview',
   'common.edit': 'Edit',
   'common.add': 'Add',
diff --git a/shared/src/i18n/es/budget.ts b/shared/src/i18n/es/budget.ts
index 9747e8e10..99bced521 100644
--- a/shared/src/i18n/es/budget.ts
+++ b/shared/src/i18n/es/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Crear categoría',
   'budget.category': 'Categoría',
   'budget.categoryName': 'Nombre de la categoría',
+  'budget.addCategory': 'Añadir categoría',
   'budget.table.name': 'Nombre',
   'budget.table.total': 'Total',
   'budget.table.persons': 'Personas',
diff --git a/shared/src/i18n/es/common.ts b/shared/src/i18n/es/common.ts
index 2ba40ca78..f79e6b99b 100644
--- a/shared/src/i18n/es/common.ts
+++ b/shared/src/i18n/es/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Cancelar',
   'common.clear': 'Borrar',
   'common.delete': 'Eliminar',
+  'common.remove': 'Eliminar',
   'common.preview': 'Vista previa',
   'common.edit': 'Editar',
   'common.add': 'Añadir',
diff --git a/shared/src/i18n/et/budget.ts b/shared/src/i18n/et/budget.ts
index 1d80ca82c..a632b1d45 100644
--- a/shared/src/i18n/et/budget.ts
+++ b/shared/src/i18n/et/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Loo kategooria',
   'budget.category': 'Kategooria',
   'budget.categoryName': 'Kategooria nimi',
+  'budget.addCategory': 'Lisa kategooria',
   'budget.table.name': 'Nimi',
   'budget.table.total': 'Kokku',
   'budget.table.persons': 'Inimesi',
diff --git a/shared/src/i18n/et/common.ts b/shared/src/i18n/et/common.ts
index 3d1f34651..62708e0d8 100644
--- a/shared/src/i18n/et/common.ts
+++ b/shared/src/i18n/et/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Tühista',
   'common.clear': 'Tühjenda',
   'common.delete': 'Kustuta',
+  'common.remove': 'Eemalda',
   'common.preview': 'Eelvaade',
   'common.edit': 'Muuda',
   'common.add': 'Lisa',
diff --git a/shared/src/i18n/fr/budget.ts b/shared/src/i18n/fr/budget.ts
index 6b57f6df6..65a07adca 100644
--- a/shared/src/i18n/fr/budget.ts
+++ b/shared/src/i18n/fr/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Créer une catégorie',
   'budget.category': 'Catégorie',
   'budget.categoryName': 'Nom de la catégorie',
+  'budget.addCategory': 'Ajouter une catégorie',
   'budget.table.name': 'Nom',
   'budget.table.total': 'Total',
   'budget.table.persons': 'Personnes',
diff --git a/shared/src/i18n/fr/common.ts b/shared/src/i18n/fr/common.ts
index 90fb4d3be..6e14e015f 100644
--- a/shared/src/i18n/fr/common.ts
+++ b/shared/src/i18n/fr/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Annuler',
   'common.clear': 'Effacer',
   'common.delete': 'Supprimer',
+  'common.remove': 'Supprimer',
   'common.preview': 'Aperçu',
   'common.edit': 'Modifier',
   'common.add': 'Ajouter',
diff --git a/shared/src/i18n/gr/budget.ts b/shared/src/i18n/gr/budget.ts
index f4d13ea65..1ccc669fb 100644
--- a/shared/src/i18n/gr/budget.ts
+++ b/shared/src/i18n/gr/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Δημιουργία Κατηγορίας',
   'budget.category': 'Κατηγορία',
   'budget.categoryName': 'Όνομα Κατηγορίας',
+  'budget.addCategory': 'Προσθήκη κατηγορίας',
   'budget.table.name': 'Όνομα',
   'budget.table.total': 'Σύνολο',
   'budget.table.persons': 'Άτομα',
diff --git a/shared/src/i18n/gr/common.ts b/shared/src/i18n/gr/common.ts
index cf4782db5..d9c1f353e 100644
--- a/shared/src/i18n/gr/common.ts
+++ b/shared/src/i18n/gr/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Ακύρωση',
   'common.clear': 'Εκκαθάριση',
   'common.delete': 'Διαγραφή',
+  'common.remove': 'Αφαίρεση',
   'common.preview': 'Προεπισκόπηση',
   'common.edit': 'Επεξεργασία',
   'common.add': 'Προσθήκη',
diff --git a/shared/src/i18n/hu/budget.ts b/shared/src/i18n/hu/budget.ts
index 459421679..4d6999e5a 100644
--- a/shared/src/i18n/hu/budget.ts
+++ b/shared/src/i18n/hu/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Kategória létrehozása',
   'budget.category': 'Kategória',
   'budget.categoryName': 'Kategória neve',
+  'budget.addCategory': 'Kategória hozzáadása',
   'budget.table.name': 'Név',
   'budget.table.total': 'Összesen',
   'budget.table.persons': 'Személyek',
diff --git a/shared/src/i18n/hu/common.ts b/shared/src/i18n/hu/common.ts
index 43a6e09d8..877030f6c 100644
--- a/shared/src/i18n/hu/common.ts
+++ b/shared/src/i18n/hu/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Mégse',
   'common.clear': 'Törlés',
   'common.delete': 'Törlés',
+  'common.remove': 'Eltávolítás',
   'common.preview': 'Előnézet',
   'common.edit': 'Szerkesztés',
   'common.add': 'Hozzáadás',
diff --git a/shared/src/i18n/i18n-catalog.spec.ts b/shared/src/i18n/i18n-catalog.spec.ts
new file mode 100644
index 000000000..83d9d9782
--- /dev/null
+++ b/shared/src/i18n/i18n-catalog.spec.ts
@@ -0,0 +1,58 @@
+// @ts-expect-error: plain .mjs script with no .d.ts; import as JS module.
+import { listDomainFiles, listLocales, parseCatalog, readCatalog } from '../../scripts/i18n-catalog.mjs';
+
+import { describe, it, expect } from 'vitest';
+
+/**
+ * The reader the i18n scripts (parity, the untranslated ratchet, the client's
+ * key check) share. It reads the tables as text, so it sees the
+ * `// en-fallback` markers, and it refuses what it cannot read rather than
+ * skipping it.
+ */
+const ROOT = new URL('../../scripts/fixtures/i18n/', import.meta.url);
+
+type Entry = { key: string; value: string; marked: boolean; line: number };
+
+describe('i18n catalogue reader', () => {
+  it('reads single-line, wrapped, double-quoted and escaped values with their markers', () => {
+    const entries = parseCatalog(
+      [
+        "  'a.one': 'One',",
+        "  'a.two':",
+        "    'Two, wrapped', // en-fallback",
+        `  'a.three': "It's",`,
+        "  'a.four': 'Don\\'t \\u00e9',",
+      ].join('\r\n'),
+    );
+    expect(entries.map((e: Entry) => [e.key, e.value, e.marked])).toEqual([
+      ['a.one', 'One', false],
+      ['a.two', 'Two, wrapped', true],
+      ['a.three', "It's", false],
+      ['a.four', "Don't é", false],
+    ]);
+  });
+
+  it('refuses a value that is not one string literal instead of skipping it', () => {
+    expect(() => parseCatalog("  'a.one': 'One' + 'Two',", 'x.ts')).toThrow(
+      /x\.ts:1: 'a\.one' is not a single string literal/,
+    );
+    expect(() => parseCatalog("  'a.one': `One`,", 'x.ts')).toThrow(/not a single string literal/);
+    expect(() => parseCatalog("  'a.one': 'unterminated,", 'x.ts')).toThrow(/not a single string literal/);
+  });
+
+  it('lists locales and domain files and reads a table from disk', () => {
+    expect(listLocales(ROOT).sort()).toEqual(['de', 'en']);
+    expect(listDomainFiles('en', ROOT)).toEqual(['a.ts']);
+    const de: Entry[] = readCatalog('de', 'a.ts', ROOT);
+    expect(de.find((e) => e.key === 'a.lone')).toMatchObject({ value: 'Remove {count} items', marked: true });
+    expect(de.find((e) => e.key === 'a.multi')).toMatchObject({
+      value: 'A long sentence that wraps onto the next line',
+    });
+  });
+
+  it('reads every real locale table', () => {
+    for (const locale of listLocales()) {
+      for (const file of listDomainFiles(locale)) expect(() => readCatalog(locale, file)).not.toThrow();
+    }
+  });
+});
diff --git a/shared/src/i18n/id/budget.ts b/shared/src/i18n/id/budget.ts
index f23297c6c..6ada99ed4 100644
--- a/shared/src/i18n/id/budget.ts
+++ b/shared/src/i18n/id/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Buat Kategori',
   'budget.category': 'Kategori',
   'budget.categoryName': 'Nama Kategori',
+  'budget.addCategory': 'Tambah kategori',
   'budget.table.name': 'Nama',
   'budget.table.total': 'Total',
   'budget.table.persons': 'Orang',
diff --git a/shared/src/i18n/id/common.ts b/shared/src/i18n/id/common.ts
index eb0642d40..5cf8e179c 100644
--- a/shared/src/i18n/id/common.ts
+++ b/shared/src/i18n/id/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Batal',
   'common.clear': 'Hapus',
   'common.delete': 'Hapus',
+  'common.remove': 'Hapus',
   'common.preview': 'Pratinjau',
   'common.edit': 'Sunting',
   'common.add': 'Tambah',
diff --git a/shared/src/i18n/it/budget.ts b/shared/src/i18n/it/budget.ts
index ef9ac2b02..726730c41 100644
--- a/shared/src/i18n/it/budget.ts
+++ b/shared/src/i18n/it/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Crea categoria',
   'budget.category': 'Categoria',
   'budget.categoryName': 'Nome categoria',
+  'budget.addCategory': 'Aggiungi categoria',
   'budget.table.name': 'Nome',
   'budget.table.total': 'Totale',
   'budget.table.persons': 'Persone',
diff --git a/shared/src/i18n/it/common.ts b/shared/src/i18n/it/common.ts
index a2ecf2858..4fd14f38a 100644
--- a/shared/src/i18n/it/common.ts
+++ b/shared/src/i18n/it/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Annulla',
   'common.clear': 'Cancella',
   'common.delete': 'Elimina',
+  'common.remove': 'Rimuovi',
   'common.preview': 'Anteprima',
   'common.edit': 'Modifica',
   'common.add': 'Aggiungi',
diff --git a/shared/src/i18n/ja/budget.ts b/shared/src/i18n/ja/budget.ts
index b9cefcdad..f0f183980 100644
--- a/shared/src/i18n/ja/budget.ts
+++ b/shared/src/i18n/ja/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'カテゴリを作成',
   'budget.category': 'カテゴリ',
   'budget.categoryName': 'カテゴリ名',
+  'budget.addCategory': 'カテゴリを追加',
   'budget.table.name': '名前',
   'budget.table.total': '合計',
   'budget.table.persons': '人数',
diff --git a/shared/src/i18n/ja/common.ts b/shared/src/i18n/ja/common.ts
index dbd28f10c..22236a113 100644
--- a/shared/src/i18n/ja/common.ts
+++ b/shared/src/i18n/ja/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'キャンセル',
   'common.clear': 'クリア',
   'common.delete': '削除',
+  'common.remove': '削除',
   'common.preview': 'プレビュー',
   'common.edit': '編集',
   'common.add': '追加',
diff --git a/shared/src/i18n/ko/budget.ts b/shared/src/i18n/ko/budget.ts
index 3db01e063..58e378e0b 100644
--- a/shared/src/i18n/ko/budget.ts
+++ b/shared/src/i18n/ko/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': '카테고리 만들기',
   'budget.category': '카테고리',
   'budget.categoryName': '카테고리 이름',
+  'budget.addCategory': '카테고리 추가',
   'budget.table.name': '이름',
   'budget.table.total': '합계',
   'budget.table.persons': '인원',
diff --git a/shared/src/i18n/ko/common.ts b/shared/src/i18n/ko/common.ts
index b99a6b02f..0cebdb73f 100644
--- a/shared/src/i18n/ko/common.ts
+++ b/shared/src/i18n/ko/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': '취소',
   'common.clear': '지우기',
   'common.delete': '삭제',
+  'common.remove': '제거',
   'common.preview': '미리보기',
   'common.edit': '편집',
   'common.add': '추가',
diff --git a/shared/src/i18n/nl/budget.ts b/shared/src/i18n/nl/budget.ts
index c6cbb1ef1..9f99e795e 100644
--- a/shared/src/i18n/nl/budget.ts
+++ b/shared/src/i18n/nl/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Categorie aanmaken',
   'budget.category': 'Categorie',
   'budget.categoryName': 'Categorienaam',
+  'budget.addCategory': 'Categorie toevoegen',
   'budget.table.name': 'Naam',
   'budget.table.total': 'Totaal',
   'budget.table.persons': 'Personen',
diff --git a/shared/src/i18n/nl/common.ts b/shared/src/i18n/nl/common.ts
index b09128a8a..172cd8912 100644
--- a/shared/src/i18n/nl/common.ts
+++ b/shared/src/i18n/nl/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Annuleren',
   'common.clear': 'Wissen',
   'common.delete': 'Verwijderen',
+  'common.remove': 'Verwijderen',
   'common.preview': 'Voorbeeld',
   'common.edit': 'Bewerken',
   'common.add': 'Toevoegen',
diff --git a/shared/src/i18n/pl/budget.ts b/shared/src/i18n/pl/budget.ts
index 5894e8dc2..ba35955c2 100644
--- a/shared/src/i18n/pl/budget.ts
+++ b/shared/src/i18n/pl/budget.ts
@@ -10,6 +10,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Utwórz kategorię',
   'budget.category': 'Kategoria',
   'budget.categoryName': 'Nazwa kategorii',
+  'budget.addCategory': 'Dodaj kategorię',
   'budget.table.name': 'Nazwa',
   'budget.table.total': 'Łącznie',
   'budget.table.persons': 'Osoby',
diff --git a/shared/src/i18n/pl/common.ts b/shared/src/i18n/pl/common.ts
index f50dc479a..87f6dae65 100644
--- a/shared/src/i18n/pl/common.ts
+++ b/shared/src/i18n/pl/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Anuluj',
   'common.clear': 'Wyczyść',
   'common.delete': 'Usuń',
+  'common.remove': 'Usuń',
   'common.preview': 'Podgląd',
   'common.edit': 'Edytuj',
   'common.add': 'Dodaj',
diff --git a/shared/src/i18n/ru/budget.ts b/shared/src/i18n/ru/budget.ts
index 2d32cb5fb..02fe11758 100644
--- a/shared/src/i18n/ru/budget.ts
+++ b/shared/src/i18n/ru/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Создать категорию',
   'budget.category': 'Категория',
   'budget.categoryName': 'Название категории',
+  'budget.addCategory': 'Добавить категорию',
   'budget.table.name': 'Название',
   'budget.table.total': 'Итого',
   'budget.table.persons': 'Человек',
diff --git a/shared/src/i18n/ru/common.ts b/shared/src/i18n/ru/common.ts
index ff8beaf7b..7db600594 100644
--- a/shared/src/i18n/ru/common.ts
+++ b/shared/src/i18n/ru/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Отмена',
   'common.clear': 'Очистить',
   'common.delete': 'Удалить',
+  'common.remove': 'Удалить',
   'common.preview': 'Предпросмотр',
   'common.edit': 'Редактировать',
   'common.add': 'Добавить',
diff --git a/shared/src/i18n/sk/budget.ts b/shared/src/i18n/sk/budget.ts
index a2f1d7b49..680363bdc 100644
--- a/shared/src/i18n/sk/budget.ts
+++ b/shared/src/i18n/sk/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Vytvoriť kategóriu',
   'budget.category': 'Kategória',
   'budget.categoryName': 'Názov kategórie',
+  'budget.addCategory': 'Pridať kategóriu',
   'budget.table.name': 'Názov',
   'budget.table.total': 'Spolu',
   'budget.table.persons': 'Osoby',
diff --git a/shared/src/i18n/sk/common.ts b/shared/src/i18n/sk/common.ts
index 2d93b96a1..2a0b5b284 100644
--- a/shared/src/i18n/sk/common.ts
+++ b/shared/src/i18n/sk/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Zrušiť',
   'common.clear': 'Vymazať',
   'common.delete': 'Odstrániť',
+  'common.remove': 'Odstrániť',
   'common.preview': 'Náhľad',
   'common.edit': 'Upraviť',
   'common.add': 'Pridať',
diff --git a/shared/src/i18n/sv/budget.ts b/shared/src/i18n/sv/budget.ts
index df6ae4578..89b9c9426 100644
--- a/shared/src/i18n/sv/budget.ts
+++ b/shared/src/i18n/sv/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Skapa kategori',
   'budget.category': 'Kategori',
   'budget.categoryName': 'Kategorinamn',
+  'budget.addCategory': 'Lägg till kategori',
   'budget.table.name': 'Namn',
   'budget.table.total': 'Totalt',
   'budget.table.persons': 'Personer',
diff --git a/shared/src/i18n/sv/common.ts b/shared/src/i18n/sv/common.ts
index 57efdcff2..987645a2c 100644
--- a/shared/src/i18n/sv/common.ts
+++ b/shared/src/i18n/sv/common.ts
@@ -19,6 +19,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Avbryt',
   'common.clear': 'Rensa',
   'common.delete': 'Ta bort',
+  'common.remove': 'Ta bort',
   'common.preview': 'Förhandsvisning',
   'common.edit': 'Redigera',
   'common.add': 'Lägg till',
diff --git a/shared/src/i18n/th/budget.ts b/shared/src/i18n/th/budget.ts
index 75fadc1be..a1e9a9992 100644
--- a/shared/src/i18n/th/budget.ts
+++ b/shared/src/i18n/th/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'สร้างหมวดหมู่',
   'budget.category': 'หมวดหมู่',
   'budget.categoryName': 'ชื่อหมวดหมู่',
+  'budget.addCategory': 'เพิ่มหมวดหมู่',
   'budget.table.name': 'ชื่อ',
   'budget.table.total': 'รวม',
   'budget.table.persons': 'บุคคล',
diff --git a/shared/src/i18n/th/common.ts b/shared/src/i18n/th/common.ts
index bfb50ad26..95a2230d2 100644
--- a/shared/src/i18n/th/common.ts
+++ b/shared/src/i18n/th/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'ยกเลิก',
   'common.clear': 'ล้าง',
   'common.delete': 'ลบ',
+  'common.remove': 'ลบ',
   'common.preview': 'ดูตัวอย่าง',
   'common.edit': 'แก้ไข',
   'common.add': 'เพิ่ม',
diff --git a/shared/src/i18n/tr/budget.ts b/shared/src/i18n/tr/budget.ts
index ab937e569..d6f20c73d 100644
--- a/shared/src/i18n/tr/budget.ts
+++ b/shared/src/i18n/tr/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Kategori Oluştur',
   'budget.category': 'Kategori',
   'budget.categoryName': 'Kategori Adı',
+  'budget.addCategory': 'Kategori ekle',
   'budget.table.name': 'İsim',
   'budget.table.total': 'Toplam',
   'budget.table.persons': 'Kişiler',
diff --git a/shared/src/i18n/tr/common.ts b/shared/src/i18n/tr/common.ts
index aaee60a54..8b527d6bb 100644
--- a/shared/src/i18n/tr/common.ts
+++ b/shared/src/i18n/tr/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'İptal',
   'common.clear': 'Temizle',
   'common.delete': 'Sil',
+  'common.remove': 'Kaldır',
   'common.preview': 'Önizleme',
   'common.edit': 'Düzenle',
   'common.add': 'Ekle',
diff --git a/shared/src/i18n/uk/budget.ts b/shared/src/i18n/uk/budget.ts
index 7b771fa6a..2f0041e00 100644
--- a/shared/src/i18n/uk/budget.ts
+++ b/shared/src/i18n/uk/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Створити категорію',
   'budget.category': 'Категорія',
   'budget.categoryName': 'Назва категорії',
+  'budget.addCategory': 'Додати категорію',
   'budget.table.name': 'Назва',
   'budget.table.total': 'Всього',
   'budget.table.persons': 'Осіб',
diff --git a/shared/src/i18n/uk/common.ts b/shared/src/i18n/uk/common.ts
index 3474b0c92..fdf6f018c 100644
--- a/shared/src/i18n/uk/common.ts
+++ b/shared/src/i18n/uk/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Скасувати',
   'common.clear': 'Очистити',
   'common.delete': 'Видалити',
+  'common.remove': 'Видалити',
   'common.preview': 'Перегляд',
   'common.edit': 'Редагувати',
   'common.add': 'Додати',
diff --git a/shared/src/i18n/vi/budget.ts b/shared/src/i18n/vi/budget.ts
index d069b8167..f9473700d 100644
--- a/shared/src/i18n/vi/budget.ts
+++ b/shared/src/i18n/vi/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': 'Tạo danh mục',
   'budget.category': 'Loại',
   'budget.categoryName': 'Tên danh mục',
+  'budget.addCategory': 'Thêm danh mục',
   'budget.table.name': 'Tên',
   'budget.table.total': 'Tổng cộng',
   'budget.table.persons': 'Người',
diff --git a/shared/src/i18n/vi/common.ts b/shared/src/i18n/vi/common.ts
index 78523743d..ad42a6759 100644
--- a/shared/src/i18n/vi/common.ts
+++ b/shared/src/i18n/vi/common.ts
@@ -19,6 +19,7 @@ const common: TranslationStrings = {
   'common.cancel': 'Hủy',
   'common.clear': 'Xóa',
   'common.delete': 'Xóa bỏ',
+  'common.remove': 'Gỡ bỏ',
   'common.preview': 'Xem trước',
   'common.edit': 'Chỉnh sửa',
   'common.add': 'Thêm',
diff --git a/shared/src/i18n/zh-TW/budget.ts b/shared/src/i18n/zh-TW/budget.ts
index d99f83747..58484d09c 100644
--- a/shared/src/i18n/zh-TW/budget.ts
+++ b/shared/src/i18n/zh-TW/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': '建立分類',
   'budget.category': '分類',
   'budget.categoryName': '分類名稱',
+  'budget.addCategory': '新增分類',
   'budget.table.name': '名稱',
   'budget.table.total': '合計',
   'budget.table.persons': '人數',
diff --git a/shared/src/i18n/zh-TW/common.ts b/shared/src/i18n/zh-TW/common.ts
index 0d7cda513..1834d5513 100644
--- a/shared/src/i18n/zh-TW/common.ts
+++ b/shared/src/i18n/zh-TW/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': '取消',
   'common.clear': '清除',
   'common.delete': '刪除',
+  'common.remove': '刪除',
   'common.preview': '預覽',
   'common.edit': '編輯',
   'common.add': '新增',
diff --git a/shared/src/i18n/zh/budget.ts b/shared/src/i18n/zh/budget.ts
index c49d1385e..afa1b93cc 100644
--- a/shared/src/i18n/zh/budget.ts
+++ b/shared/src/i18n/zh/budget.ts
@@ -11,6 +11,7 @@ const budget: TranslationStrings = {
   'budget.createCategory': '创建分类',
   'budget.category': '分类',
   'budget.categoryName': '分类名称',
+  'budget.addCategory': '添加分类',
   'budget.table.name': '名称',
   'budget.table.total': '合计',
   'budget.table.persons': '人数',
diff --git a/shared/src/i18n/zh/common.ts b/shared/src/i18n/zh/common.ts
index 3aeaf542e..8814437f5 100644
--- a/shared/src/i18n/zh/common.ts
+++ b/shared/src/i18n/zh/common.ts
@@ -7,6 +7,7 @@ const common: TranslationStrings = {
   'common.cancel': '取消',
   'common.clear': '清除',
   'common.delete': '删除',
+  'common.remove': '删除',
   'common.preview': '预览',
   'common.edit': '编辑',
   'common.add': '添加',