diff --git a/tests/backup_i18n_seam.cjs b/tests/backup_i18n_seam.cjs
new file mode 100644
index 00000000..3404efe2
--- /dev/null
+++ b/tests/backup_i18n_seam.cjs
@@ -0,0 +1,40 @@
+// Test-only provider seam shared by independent backup message programs.
+// Compile only checked-out provider source; catalog values are never executable code.
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const { createRequire } = require('node:module');
+const app = path.resolve(__dirname, '../AppImage');
+const ts = createRequire(path.join(app, 'package.json'))('typescript');
+const read = file => fs.readFileSync(path.join(app, file), 'utf8');
+const compile = text => ts.transpileModule(text, {
+  compilerOptions: { module: ts.ModuleKind.CommonJS, target: ts.ScriptTarget.ES2020, jsx: ts.JsxEmit.React },
+}).outputText;
+const printer = ts.createPrinter();
+const provider = ts.createSourceFile('provider.tsx', read('lib/i18n/provider.tsx'), ts.ScriptTarget.Latest, true, ts.ScriptKind.TSX);
+const pure = provider.statements.filter(node => ts.isFunctionDeclaration(node) &&
+  ['getMessage', 'interpolate'].includes(node.name?.text));
+assert.equal(pure.length, 2);
+let lookup;
+function visitLookup(node) {
+  if (ts.isVariableDeclaration(node) && node.name.getText(provider) === 't' &&
+      node.initializer && ts.isCallExpression(node.initializer) &&
+      node.initializer.expression.getText(provider) === 'useCallback') lookup = node.initializer.arguments[0];
+  ts.forEachChild(node, visitLookup);
+}
+visitLookup(provider);
+assert.ok(lookup, 'real provider lookup callback');
+const lookupCode = pure.map(node => printer.printNode(ts.EmitHint.Unspecified, node, provider)).join('\n') +
+  '\nconst t = ' + printer.printNode(ts.EmitHint.Expression, lookup, provider) + ';';
+const catalogs = Object.fromEntries(fs.readdirSync(path.join(app, 'messages')).filter(locale =>
+  fs.existsSync(path.join(app, 'messages', locale, 'common.json'))).map(locale =>
+  [locale, JSON.parse(read(`messages/${locale}/common.json`))]));
+const registered = provider.statements.flatMap(statement => ts.isVariableStatement(statement) ?
+  statement.declarationList.declarations.filter(declaration => declaration.name.getText(provider) === 'MESSAGE_CATALOG') : []);
+assert.equal(registered.length, 1, 'real provider catalog declaration');
+assert.deepEqual(registered[0].initializer.properties.map(property => property.name.getText(provider)).sort(),
+  Object.keys(catalogs).sort(), 'test each runtime-registered shipped locale');
+assert.ok(catalogs.en, 'English fallback catalog exists');
+const translator = (language, messages = catalogs) =>
+  new Function('MESSAGE_CATALOG', 'language', compile(lookupCode) + '\nreturn t;')(messages, language);
+module.exports = { app, ts, read, compile, printer, catalogs, translator };
diff --git a/tests/test_audit_report.py b/tests/test_audit_report.py
index 5c12e438..c6bd5cf6 100644
--- a/tests/test_audit_report.py
+++ b/tests/test_audit_report.py
@@ -395,8 +395,38 @@ class StoreTests(unittest.TestCase):
         critical = self.finding()
         critical.update(classification='critical', raw_classification='critical')
         changed = self.recorded(critical)
-        self.assertEqual(len(engine.compare_runs(before, changed)['new']), 1)
-        self.assertEqual(len(engine.compare_runs(changed, before)['new']), 1)
+        worse = engine.compare_runs(before, changed)
+        self.assertEqual(worse['new'], [])
+        self.assertEqual(worse['resolved'], [])
+        self.assertEqual(len(worse['worse']), 1)
+        self.assertEqual(worse['worse'][0]['classification'], 'critical')
+        self.assertEqual(worse['worse'][0]['previous_classification'], 'warning')
+        self.assertEqual(worse['worse'][0]['previous_affected'], 1)
+        self.assertEqual(worse['worse'][0]['affected_count'], 1)
+        self.assertEqual(worse['better'], [])
+        better = engine.compare_runs(changed, before)
+        self.assertEqual(better['new'], [])
+        self.assertEqual(better['resolved'], [])
+        self.assertEqual(len(better['better']), 1)
+        self.assertEqual(better['better'][0]['classification'], 'warning')
+        self.assertEqual(better['better'][0]['previous_classification'], 'critical')
+        self.assertEqual(better['better'][0]['previous_affected'], 1)
+        self.assertEqual(better['better'][0]['affected_count'], 1)
+        self.assertEqual(better['worse'], [])
+
+    def test_new_failure_and_verified_resolution_stay_distinct(self):
+        conformant = self.recorded(self.finding(state='pass'))
+        warning = self.recorded(self.finding())
+        new = engine.compare_runs(conformant, warning)
+        self.assertEqual(len(new['new']), 1)
+        self.assertEqual(new['new'][0]['classification'], 'warning')
+        self.assertEqual(new['resolved'], [])
+        self.assertEqual(new['unverified'], [])
+        resolved = engine.compare_runs(warning, conformant)
+        self.assertEqual(len(resolved['resolved']), 1)
+        self.assertEqual(resolved['resolved'][0]['classification'], 'conformant')
+        self.assertEqual(resolved['new'], [])
+        self.assertEqual(resolved['unverified'], [])
 
     def test_malformed_result_does_not_abort_remaining_checks(self):
         for bad in (False, [], {'affected': [None]}, {'affected': 'invalid'}):
diff --git a/tests/test_backup_archives_empty.cjs b/tests/test_backup_archives_empty.cjs
index c78c5797..66b126ea 100644
--- a/tests/test_backup_archives_empty.cjs
+++ b/tests/test_backup_archives_empty.cjs
@@ -2,38 +2,8 @@
 // No component imports, React effects, API calls or host-management execution.
 // Run from the repository root: node tests/test_backup_archives_empty.cjs
 const assert = require('node:assert/strict');
-const fs = require('node:fs');
-const path = require('node:path');
-const { createRequire } = require('node:module');
-const app = path.resolve(__dirname, '../AppImage');
-const ts = createRequire(path.join(app, 'package.json'))('typescript');
-const read = file => fs.readFileSync(path.join(app, file), 'utf8');
+const { ts, read, compile, printer, catalogs, translator } = require('./backup_i18n_seam.cjs');
 const parse = file => ts.createSourceFile(file, read(file), ts.ScriptTarget.Latest, true, ts.ScriptKind.TSX);
-const compile = text => ts.transpileModule(text, {
-  compilerOptions: { module: ts.ModuleKind.CommonJS, target: ts.ScriptTarget.ES2020, jsx: ts.JsxEmit.React },
-}).outputText;
-const printer = ts.createPrinter();
-const provider = parse('lib/i18n/provider.tsx');
-const pure = provider.statements.filter(node => ts.isFunctionDeclaration(node) &&
-  ['getMessage', 'interpolate'].includes(node.name?.text));
-assert.equal(pure.length, 2);
-let lookup;
-function visitLookup(node) {
-  if (ts.isVariableDeclaration(node) && node.name.getText(provider) === 't' &&
-      node.initializer && ts.isCallExpression(node.initializer) &&
-      node.initializer.expression.getText(provider) === 'useCallback') lookup = node.initializer.arguments[0];
-  ts.forEachChild(node, visitLookup);
-}
-visitLookup(provider);
-assert.ok(lookup, 'real provider lookup callback');
-const lookupCode = pure.map(node => printer.printNode(ts.EmitHint.Unspecified, node, provider)).join('\n') +
-  '\nconst t = ' + printer.printNode(ts.EmitHint.Expression, lookup, provider) + ';';
-const catalogs = Object.fromEntries(fs.readdirSync(path.join(app, 'messages')).filter(locale =>
-  fs.existsSync(path.join(app, 'messages', locale, 'common.json'))).map(locale =>
-  [locale, JSON.parse(read(`messages/${locale}/common.json`))]));
-// Compile only trusted, checked-out source; no catalog/input strings enter code.
-const translator = (language, messages = catalogs) =>
-  new Function('MESSAGE_CATALOG', 'language', compile(lookupCode) + '\nreturn t;')(messages, language);
 
 const source = parse('components/host-backup.tsx');
 let branch;
@@ -68,16 +38,22 @@ const text = (locale = 'en', overrides = {}, messages = catalogs) => {
     state.archivesResp, state.remoteArchivesResp, state.unifiedArchives);
 };
 
-assert.equal(text(), 'No backup archives found.');
-assert.equal(text('it'), 'No backup archives found.', 'Italian catalog uses English fallback');
-// Keep fallback coverage even after all shipped locales gain the new key.
-assert.equal(text('missing', {}, { ...catalogs, missing: {} }), 'No backup archives found.');
-for (const locale of Object.keys(catalogs)) {
-  // Existing catalogs intentionally have no new key; actual provider falls back.
-  if (catalogs[locale].backup?.archives?.emptyMessage === undefined) {
-    assert.equal(text(locale), 'No backup archives found.', `${locale}: missing-key fallback`);
-  }
+const emptyMessage = 'No backup archives found.';
+assert.equal(catalogs.en.backup.archives.emptyMessage, emptyMessage);
+assert.equal(text(), emptyMessage);
+// Missing-key fallback is unconditional: it must survive later catalog generation.
+assert.equal(text('missing', {}, { ...catalogs, missing: {} }), emptyMessage);
+const synthetic = { ...catalogs, fixture: { backup: { archives: { emptyMessage: 'Fixture: no archives.' } } } };
+assert.equal(text('fixture', {}, synthetic), 'Fixture: no archives.');
+const locales = Object.keys(catalogs);
+assert.ok(locales.length > 1, 'shipped multilingual catalogs discovered');
+for (const locale of locales) {
+  const shipped = catalogs[locale].backup?.archives?.emptyMessage;
+  assert.equal(text(locale), shipped ?? emptyMessage, `${locale}: actual shipped locale or English fallback`);
 }
+assert.ok(locales.some(locale => locale !== 'en' &&
+  typeof catalogs[locale].backup?.archives?.emptyMessage === 'string' &&
+  catalogs[locale].backup.archives.emptyMessage !== emptyMessage), 'localized shipped archive message exercised');
 for (const count of [1, 3]) assert.equal(text('en', { unifiedArchives: Array(count).fill({}) }), 'NONEMPTY_ARCHIVES');
 assert.equal(text('en', { archivesResp: undefined, remoteArchivesResp: undefined }), translator('en')('backup.common.loading'));
 assert.equal(text('en', { archivesErr: true, remoteArchivesErr: true }), translator('en')('backup.archives.loadFailed'));
@@ -86,6 +62,4 @@ assert.equal(text('en', { archivesErr: true, archivesResp: undefined }), 'No bac
 assert.equal(text('en', { remoteArchivesErr: true, remoteArchivesResp: undefined }), 'No backup archives found.');
 assert.equal(translator('en')('backup.manual.run'), 'Run');
 assert.ok(read('components/host-backup.tsx').includes('{t("backup.manual.run")}'), 'manual action remains');
-console.log('PASS: actual archives JSX seam, zero/one/multiple, loading/errors, locale fallback, Run unchanged');
-// Export only test seams for separate, unapplied linguistic proposal checks.
-module.exports = { text, translator, catalogs };
+console.log('PASS: actual archives JSX seam, zero/one/multiple, loading/errors, shipped locales and synthetic fallback/translation, Run unchanged');
diff --git a/tests/test_backup_destination_messages.cjs b/tests/test_backup_destination_messages.cjs
index c1cc8e92..f2eb8679 100644
--- a/tests/test_backup_destination_messages.cjs
+++ b/tests/test_backup_destination_messages.cjs
@@ -1,13 +1,8 @@
 // Offline actual JSX/provider seams; no component/backend imports or effects.
 const assert = require('node:assert/strict');
-const fs = require('node:fs');
-const path = require('node:path');
-const { createRequire } = require('node:module');
-const { translator, catalogs } = require('./test_backup_archives_empty.cjs');
-const app = path.resolve(__dirname, '../AppImage');
-const ts = createRequire(path.join(app, 'package.json'))('typescript');
-const source = ts.createSourceFile('host-backup.tsx', fs.readFileSync(path.join(app, 'components/host-backup.tsx'), 'utf8'), ts.ScriptTarget.Latest, true, ts.ScriptKind.TSX);
-const printer = ts.createPrinter();
+const { ts, read, printer, translator, catalogs } = require('./backup_i18n_seam.cjs');
+const source = ts.createSourceFile('host-backup.tsx', read('components/host-backup.tsx'), ts.ScriptTarget.Latest, true, ts.ScriptKind.TSX);
+
 const React = { createElement: (tag, props, ...children) => children.flat(Infinity).filter(x => x != null && x !== false).join('') };
 function find(predicate) {
   const found = [];
@@ -25,32 +20,45 @@ function render(node, locale, backups = 1, messages = catalogs) {
 }
 const kept = find(node => ts.isBinaryExpression(node) && node.left.getText(source) === 'backups > 0');
 const keptMessage = 'Existing backup archives are not deleted.';
-for (const count of [1, 3]) assert.equal(render(kept, 'it', count), keptMessage, 'Italian catalog uses English fallback');
+assert.equal(catalogs.en.backup.destinations.backupsKeptMessage, keptMessage);
+assert.equal(render(kept, 'en', 1), keptMessage);
+assert.equal(render(kept, 'en', 3), keptMessage);
 assert.equal(render(kept, 'en', 0), false);
-for (const locale of Object.keys(catalogs)) {
-  if (catalogs[locale].backup?.destinations?.backupsKeptMessage !== undefined && locale !== 'en') continue;
-  for (const count of [1, 3]) assert.equal(render(kept, locale, count), keptMessage, `${locale}: kept whole-message fallback`);
-}
-console.log('PASS: destination removal JSX guard 0/1/N and whole-message locale fallback');
+// A missing locale key must use English regardless of shipped catalog completeness.
+const missing = { ...catalogs, missing: {} };
+for (const count of [1, 3]) assert.equal(render(kept, 'missing', count, missing), keptMessage);
+console.log('PASS: destination removal JSX guard 0/1/N and missing-key fallback');
 // Select the actual help paragraph, keeping its literal paths/JSX whitespace.
 const help = find(node => ts.isJsxElement(node) && node.openingElement.tagName.getText(source) === 'p' &&
   /backup\.destinations\.localAttachHelp(?:Before|Message)/.test(node.getText(source)));
 const helpMessage = 'Mount USB drives first. Leave blank to use the PVE storage path + /dump (fallback: /var/lib/vz/dump).';
-assert.equal(render(help, 'it'), helpMessage, 'Italian catalog uses English fallback');
-for (const locale of Object.keys(catalogs)) {
-  if (catalogs[locale].backup?.destinations?.localAttachHelpMessage !== undefined && locale !== 'en') continue;
-  assert.equal(render(help, locale), helpMessage, `${locale}: local attach help fallback`);
-}
-// Missing-key fallback must remain covered after shipped catalogs are complete.
-const missing = { ...catalogs, missing: {} };
-assert.equal(render(kept, 'missing', 1, missing), keptMessage);
+assert.equal(catalogs.en.backup.destinations.localAttachHelpMessage, helpMessage);
+assert.equal(render(help, 'en'), helpMessage);
 assert.equal(render(help, 'missing', 1, missing), helpMessage);
-// Synthetic locale proves complete messages are translatable, not hardcoded.
+// Synthetic whole messages prove both JSX consumers use the provider rather than hardcoded English.
 const synthetic = { ...catalogs, fixture: { backup: { destinations: {
   backupsKeptMessage: 'Fixture kept.', localAttachHelpMessage: 'Fixture help.',
 } } } };
 assert.equal(render(kept, 'fixture', 1, synthetic), 'Fixture kept.');
+assert.equal(render(kept, 'fixture', 3, synthetic), 'Fixture kept.');
 assert.equal(render(help, 'fixture', 1, synthetic), 'Fixture help.');
+const locales = Object.keys(catalogs);
+assert.ok(locales.length > 1, 'shipped multilingual catalogs discovered');
+for (const locale of locales) {
+  const destinations = catalogs[locale].backup?.destinations;
+  for (const count of [1, 3]) {
+    assert.equal(render(kept, locale, count), destinations?.backupsKeptMessage ?? keptMessage,
+      `${locale}: actual kept message or English fallback`);
+  }
+  assert.equal(render(help, locale), destinations?.localAttachHelpMessage ?? helpMessage,
+    `${locale}: actual local attach help or English fallback`);
+}
+for (const [key, english] of [['backupsKeptMessage', keptMessage], ['localAttachHelpMessage', helpMessage]]) {
+  assert.ok(locales.some(locale => locale !== 'en' &&
+    typeof catalogs[locale].backup?.destinations?.[key] === 'string' &&
+    catalogs[locale].backup.destinations[key] !== english),
+    `${key}: localized shipped message exercised`);
+}
 assert.equal(catalogs.en.backup.destinations.kept, 'kept');
 assert.equal(catalogs.en.backup.destinations.localAttachHelpMiddle, 'USB drives');
-console.log('PASS: local attach JSX whole-message fallback and literal paths');
+console.log('PASS: destination whole-message JSX, shipped locales, synthetic translation/fallback and literal paths');