diff --git a/scripts/promote-vsix.cjs b/scripts/promote-vsix.cjs
index d1b59a7..d5e70d8 100644
--- a/scripts/promote-vsix.cjs
+++ b/scripts/promote-vsix.cjs
@@ -6,7 +6,22 @@ const path = require('node:path');
 const { createHash } = require('node:crypto');
 const { verifyRun, prepareReleaseAssets, renderReleaseNotes, verifyValidationJobs } = require('./release-candidate');
 const { evidenceNames } = require('./ci-validation.cjs');
-const { command, api, optionalApi, pages, git, currentMain, assertMain, assertRepository, REPOSITORY } = require('./release-github.cjs');
+const { command, api, optionalApi, pages, findRelease, git, currentMain, assertMain, assertRepository, REPOSITORY } = require('./release-github.cjs');
+
+// An interrupted upload can leave a draft without a Git tag, so check the
+// release list as well as the tag before creating anything.
+function assertUnreleased(tag, client = { pages, optionalApi }) {
+    assert.equal(findRelease(tag, client), null, 'A release or draft already exists; do not replace it');
+    assert.equal(client.optionalApi(`git/ref/tags/${tag}`), null, 'A tag already exists; do not move it');
+}
+
+function confirmRelease(tag, publish, client = { pages }) {
+    const release = findRelease(tag, client);
+    assert.ok(release, `No release or draft for ${tag} was found after upload`);
+    assert.equal(release.draft, !publish, publish ? `${tag} is still a draft` : `${tag} is public, not a draft`);
+    assert.equal(release.prerelease, false, `${tag} is marked as a prerelease`);
+    return release;
+}
 
 async function promote({ runId, publish = false, beforePublish = async () => {} }) {
     assertRepository();
@@ -21,8 +36,7 @@ async function promote({ runId, publish = false, beforePublish = async () => {}
     const version = JSON.parse(fs.readFileSync('package.json', 'utf8')).version;
     const tag = 'v' + version;
     const notes = fs.readFileSync(`release-notes/${version}.md`, 'utf8');
-    assert.equal(optionalApi(`releases/tags/${tag}`), null, 'A release or draft already exists; do not replace it');
-    assert.equal(optionalApi(`git/ref/tags/${tag}`), null, 'A tag already exists; do not move it');
+    assertUnreleased(tag);
     const directory = fs.mkdtempSync(path.join(os.tmpdir(), 'vsix-release-'));
     try {
         const dist = path.join(directory, 'dist');
@@ -67,9 +81,7 @@ async function promote({ runId, publish = false, beforePublish = async () => {}
             await beforePublish();
             command('gh', ['release', 'edit', tag, '--repo', REPOSITORY, '--draft=false', '--latest']);
         }
-        const released = api(`releases/tags/${tag}`);
-        assert.equal(released.draft, !publish);
-        assert.equal(released.prerelease, false);
+        const released = confirmRelease(tag, publish);
         console.log(`${publish ? 'Published' : 'Prepared draft'} ${released.html_url} from ${source}`);
         if (process.env.GITHUB_STEP_SUMMARY) fs.appendFileSync(process.env.GITHUB_STEP_SUMMARY,
             `\n${publish ? 'Published' : 'Prepared draft'} [${tag}](${released.html_url}) from \`${source}\`.\n`);
@@ -83,4 +95,4 @@ if (require.main === module) promote({ runId: process.env.VALIDATION_RUN }).catc
     if (error.stderr) console.error(String(error.stderr));
     process.exitCode = 1;
 });
-module.exports = { promote };
+module.exports = { promote, assertUnreleased, confirmRelease };
diff --git a/scripts/release-github.cjs b/scripts/release-github.cjs
index ac67d92..7facab1 100644
--- a/scripts/release-github.cjs
+++ b/scripts/release-github.cjs
@@ -24,6 +24,14 @@ function pages(endpoint, key) {
     const result = JSON.parse(command('gh', ['api', '--paginate', '--slurp', `repos/${REPOSITORY}/${endpoint}`]));
     return result.flatMap(page => key ? page[key] : page);
 }
+// GET releases/tags/{tag} omits drafts, which have no Git tag until they are
+// published. The authenticated release list includes drafts for workflows
+// with contents write permission, so release identity checks search it.
+function findRelease(tag, client = { pages }) {
+    const matches = client.pages('releases?per_page=100').filter(release => release.tag_name === tag);
+    assert.ok(matches.length <= 1, `${matches.length} releases or drafts use ${tag}; inspect them before continuing`);
+    return matches[0] || null;
+}
 function git(...args) { return command('git', args); }
 function currentMain() {
     const sha = api('git/ref/heads/main').object.sha;
@@ -36,4 +44,4 @@ function assertMain(source) {
 function assertRepository() {
     assert.equal(process.env.GITHUB_REPOSITORY, REPOSITORY);
 }
-module.exports = { REPOSITORY, command, api, optionalApi, pages, git, currentMain, assertMain, assertRepository };
+module.exports = { REPOSITORY, command, api, optionalApi, pages, findRelease, git, currentMain, assertMain, assertRepository };
diff --git a/test/specs/command-palette.spec.ts b/test/specs/command-palette.spec.ts
index 1ee46cd..8ffb42a 100644
--- a/test/specs/command-palette.spec.ts
+++ b/test/specs/command-palette.spec.ts
@@ -91,7 +91,8 @@ test.describe('コマンドパレット', () => {
         await editor.focus();
         const modifier = process.platform === 'darwin' ? 'Meta' : 'Control';
         await page.keyboard.press(`${modifier}+/`);
-        await page.waitForTimeout(100);
+        // Opening the palette moves focus on the next animation frame.
+        await expect(page.locator('.command-palette-input')).toBeFocused();
 
         // 最初のアイテムが選択されている
         const firstItem = page.locator('.command-palette-item').first();
@@ -186,7 +187,8 @@ test.describe('コマンドパレット', () => {
         // カーソルは「行2」にある
         const modifier = process.platform === 'darwin' ? 'Meta' : 'Control';
         await page.keyboard.press(`${modifier}+/`);
-        await page.waitForTimeout(100);
+        // Opening the palette moves focus on the next animation frame.
+        await expect(page.locator('.command-palette-input')).toBeFocused();
 
         // Esc で閉じた後、カーソル位置は「行2」のまま
         await page.keyboard.press('Escape');
diff --git a/test/unit/release-lookup.test.js b/test/unit/release-lookup.test.js
new file mode 100644
index 0000000..03c9f7e
--- /dev/null
+++ b/test/unit/release-lookup.test.js
@@ -0,0 +1,67 @@
+'use strict';
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const { findRelease } = require('../../scripts/release-github.cjs');
+const { assertUnreleased, confirmRelease } = require('../../scripts/promote-vsix.cjs');
+
+const release = (overrides = {}) => ({ id: 1, tag_name: 'v0.9.1', draft: false, prerelease: false,
+    html_url: 'https://github.com/BinaryOutlook/binary-markdown/releases/tag/v0.9.1', ...overrides });
+const draft = overrides => release({ draft: true,
+    html_url: 'https://github.com/BinaryOutlook/binary-markdown/releases/tag/untagged-0123456789abcdef', ...overrides });
+
+// GitHub's releases/tags endpoint omits drafts. The fixture exposes only the
+// release list and tag refs, so any use of that endpoint fails the test.
+function client(releases, tags = []) {
+    const calls = [];
+    return {
+        calls,
+        pages(endpoint) {
+            calls.push(endpoint);
+            assert.equal(endpoint, 'releases?per_page=100');
+            return releases;
+        },
+        optionalApi(endpoint) {
+            calls.push(endpoint);
+            const tag = endpoint.match(/^git\/ref\/tags\/(.+)$/)?.[1];
+            assert.ok(tag, 'Unexpected request: ' + endpoint);
+            return tags.includes(tag) ? { ref: `refs/tags/${tag}` } : null;
+        },
+    };
+}
+
+test('finds a draft by tag from the release list', () => {
+    const github = client([release({ id: 2, tag_name: 'v0.9.0' }), draft({ id: 3 })]);
+    assert.equal(findRelease('v0.9.1', github).id, 3);
+    assert.equal(findRelease('v0.9.2', github), null);
+});
+test('refuses to choose between releases or drafts that share a tag', () => {
+    const github = client([draft({ id: 3 }), draft({ id: 4 })]);
+    assert.throws(() => findRelease('v0.9.1', github), /2 releases or drafts use v0\.9\.1/);
+});
+test('a prepared draft confirms the manual draft workflow', () => {
+    const prepared = draft({ id: 3 });
+    assert.equal(confirmRelease('v0.9.1', false, client([prepared])), prepared);
+});
+test('automatic publication requires the release to be public', () => {
+    const published = release({ id: 3 });
+    assert.equal(confirmRelease('v0.9.1', true, client([published])), published);
+    assert.throws(() => confirmRelease('v0.9.1', true, client([draft({ id: 3 })])), /v0\.9\.1 is still a draft/);
+});
+test('a missing, unexpectedly public or prerelease result fails confirmation', () => {
+    assert.throws(() => confirmRelease('v0.9.1', false, client([])), /No release or draft for v0\.9\.1/);
+    assert.throws(() => confirmRelease('v0.9.1', false, client([release({ id: 3 })])), /v0\.9\.1 is public, not a draft/);
+    assert.throws(() => confirmRelease('v0.9.1', false, client([draft({ prerelease: true })])),
+        /v0\.9\.1 is marked as a prerelease/);
+});
+test('a leftover untagged draft blocks a new upload', () => {
+    const github = client([draft({ id: 3 })]);
+    assert.throws(() => assertUnreleased('v0.9.1', github), /A release or draft already exists/);
+});
+test('an existing tag blocks a new upload', () => {
+    assert.throws(() => assertUnreleased('v0.9.1', client([], ['v0.9.1'])), /A tag already exists/);
+});
+test('an unused version passes both upload guards', () => {
+    const github = client([release({ id: 2, tag_name: 'v0.9.0' })], ['v0.9.0']);
+    assertUnreleased('v0.9.1', github);
+    assert.deepEqual(github.calls, ['releases?per_page=100', 'git/ref/tags/v0.9.1']);
+});