diff --git a/apps/api/src/lib/manifest.ts b/apps/api/src/lib/manifest.ts
index 1c1eb02..100b62a 100644
--- a/apps/api/src/lib/manifest.ts
+++ b/apps/api/src/lib/manifest.ts
@@ -249,7 +249,12 @@ export async function resolveManifestFromReleaseAssets(
   if (assets.length === 0) return null
   const byName = new Map(assets.map((a) => [a.name, a]))
   for (const candidate of manifestCandidates()) {
-    const asset = byName.get(candidate.path)
+    // GitHub rejects release asset names with a leading dot and silently
+    // renames them on upload (".tabularium" → "default.tabularium"), so a
+    // dotfile candidate must also match its renamed form.
+    const asset =
+      byName.get(candidate.path) ??
+      (candidate.path.startsWith('.') ? byName.get(`default${candidate.path}`) : undefined)
     if (!asset) continue
     try {
       const got = await fetchAssetContent(asset.url, accessToken)
diff --git a/apps/api/src/lib/refresh-manifest.ts b/apps/api/src/lib/refresh-manifest.ts
index db71f5a..380179f 100644
--- a/apps/api/src/lib/refresh-manifest.ts
+++ b/apps/api/src/lib/refresh-manifest.ts
@@ -39,17 +39,28 @@ export async function refreshManifestForPlugin(
     if (e instanceof OAuthExpiredError) return { status: 401, body: reauthErrorBody(e) }
     throw e
   }
-  const branch = options.branch ?? plugin.latestVersion ?? 'HEAD'
-  let manifest
+  // latestVersion stores the bare semver ("0.1.1") while release tags are
+  // commonly v-prefixed ("v0.1.1") — try both when we derived the ref ourselves.
+  const gitRefs = options.branch
+    ? [options.branch]
+    : plugin.latestVersion
+      ? [plugin.latestVersion, `v${plugin.latestVersion}`]
+      : ['HEAD']
+  let manifest: Awaited<ReturnType<typeof resolveManifest>> = null
+  let branch = gitRefs[0]
   try {
-    manifest = await resolveManifest(token, ref, { ref: branch })
+    for (const gitRef of gitRefs) {
+      branch = gitRef
+      manifest = await resolveManifest(token, ref, { ref: gitRef })
+      if (manifest) break
+    }
   } catch (e) {
     if (e instanceof UpstreamUnauthorizedError) return { status: 401, body: reauthErrorBody(e) }
     if (e instanceof ManifestValidationError) return { status: 422, body: { error: e.message } }
     throw e
   }
   if (!manifest) {
-    return { status: 404, body: { error: `No .tabularium file found in ${plugin.repoUrl} @ ${branch}` } }
+    return { status: 404, body: { error: `No .tabularium file found in ${plugin.repoUrl} @ ${gitRefs.join(' or ')}` } }
   }
   const patch = manifestPatch(manifest, { repoBase: rawContentBase(ref, branch), version: branch })
   await applyManifestToPlugin(plugin.id, patch)
diff --git a/apps/api/tests/lib/asset-manifest.test.ts b/apps/api/tests/lib/asset-manifest.test.ts
index 1e86532..aa92ebd 100644
--- a/apps/api/tests/lib/asset-manifest.test.ts
+++ b/apps/api/tests/lib/asset-manifest.test.ts
@@ -42,6 +42,17 @@ describe('resolveManifestFromReleaseAssets', () => {
     spy.mockRestore()
   })
 
+  it('matches the GitHub-renamed form of a dotfile candidate (default.tabularium)', async () => {
+    const spy = mockAssetFetch({
+      'https://example.com/default.tabularium': { body: SAMPLE_JSON },
+    })
+    const manifest = await resolveManifestFromReleaseAssets('test-token', [
+      { name: 'default.tabularium', url: 'https://example.com/default.tabularium' },
+    ])
+    expect(manifest?.parsed.name).toBe('alpha')
+    spy.mockRestore()
+  })
+
   it('returns null when no asset name matches the candidate list', async () => {
     const spy = mockAssetFetch({})
     const manifest = await resolveManifestFromReleaseAssets('test-token', [
diff --git a/apps/api/tests/lib/refresh-manifest-tag.test.ts b/apps/api/tests/lib/refresh-manifest-tag.test.ts
new file mode 100644
index 0000000..b188d5d
--- /dev/null
+++ b/apps/api/tests/lib/refresh-manifest-tag.test.ts
@@ -0,0 +1,48 @@
+import { describe, it, expect, beforeEach, spyOn } from 'bun:test'
+import { clearDb, makeUser, makePlugin } from '../helpers'
+import { db } from '../../src/db'
+import { refreshManifestForPlugin } from '../../src/lib/refresh-manifest'
+
+const SAMPLE_JSON = JSON.stringify({
+  name: 'alpha',
+  version: '1.0.0',
+  description: 'A test plugin.',
+  category: 'misc',
+  icon: 'https://example.com/icon.svg',
+})
+
+// latestVersion is the bare semver ("1.0.0") but the git tag is v-prefixed
+// ("v1.0.0") — the refresh must fall back to the v-prefixed ref.
+describe('refreshManifestForPlugin tag fallback', () => {
+  beforeEach(clearDb)
+
+  it('falls back to v-prefixed tag when the bare version ref 404s', async () => {
+    const u = await makeUser()
+    const plugin = await makePlugin(u.id, { id: 'alpha', latestVersion: '1.0.0' })
+    const spy = spyOn(global, 'fetch').mockImplementation((async (url: string | URL | Request) => {
+      const key = typeof url === 'string' ? url : url instanceof URL ? url.toString() : url.url
+      if (key.includes('contents/.tabularium') && key.includes('ref=v1.0.0')) {
+        return new Response(SAMPLE_JSON, { status: 200 })
+      }
+      return new Response('not found', { status: 404 })
+    }) as unknown as typeof fetch)
+
+    const result = await refreshManifestForPlugin(plugin, {})
+    expect(result).toEqual({ ok: true, slug: 'alpha', ref: 'v1.0.0' })
+    const row = await db.query.plugins.findFirst({ where: { id: 'alpha' } })
+    expect(row?.iconUrl).toBe('https://example.com/icon.svg')
+    spy.mockRestore()
+  })
+
+  it('still 404s with both tried refs in the message when neither exists', async () => {
+    const u = await makeUser()
+    const plugin = await makePlugin(u.id, { id: 'alpha', latestVersion: '1.0.0' })
+    const spy = spyOn(global, 'fetch').mockImplementation((async () =>
+      new Response('not found', { status: 404 })) as unknown as typeof fetch)
+
+    const result = await refreshManifestForPlugin(plugin, {})
+    expect(result).toMatchObject({ status: 404 })
+    expect((result as { body: { error: string } }).body.error).toContain('1.0.0 or v1.0.0')
+    spy.mockRestore()
+  })
+})