diff --git a/packages/hydrooj/src/handler/home.ts b/packages/hydrooj/src/handler/home.ts
index 35ec353a0..b4c7a5db2 100644
--- a/packages/hydrooj/src/handler/home.ts
+++ b/packages/hydrooj/src/handler/home.ts
@@ -310,10 +310,11 @@ class HomeDomainCreateHandler extends Handler {
     @param('name', Types.Title)
     @param('bulletin', Types.Content)
     @param('avatar', Types.Content, true, isEmail)
+    // eslint-disable-next-line @typescript-eslint/no-shadow
     async post(_: string, id: string, name: string, bulletin: string, avatar: string) {
         const doc = await domain.get(id);
         if (doc) throw new DomainAlreadyExistsError(id);
-        avatar = avatar || this.user.avatar || `gravatar:${this.user.mail}` || 'gravatar:guest@hydro.local';
+        avatar = avatar || this.user.avatar || `gravatar:${this.user.mail}`;
         const domainId = await domain.add(id, this.user._id, name, bulletin);
         await domain.edit(domainId, { avatar });
         await domain.setUserRole(domainId, this.user._id, 'root');
diff --git a/packages/ui-default/build/main.js b/packages/ui-default/build/main.js
index 0961a2bf8..5fa6fcfe0 100644
--- a/packages/ui-default/build/main.js
+++ b/packages/ui-default/build/main.js
@@ -71,7 +71,7 @@ async function runGulp() {
 async function main() {
   const dir = process.cwd();
   process.chdir(root());
-  await runGulp({});
+  await runGulp();
   await runWebpack(argv);
   process.chdir(dir);
 }
diff --git a/packages/ui-default/pages/problem_edit.page.js b/packages/ui-default/pages/problem_edit.page.js
index fce4280a6..7070a7991 100644
--- a/packages/ui-default/pages/problem_edit.page.js
+++ b/packages/ui-default/pages/problem_edit.page.js
@@ -62,7 +62,7 @@ function parseCategorySelection() {
     else if (!subcategory) {
       categories[category].select = true;
       dirtyCategories.push({ type: 'category', category });
-    } else if (category) {
+    } else {
       categories[category].children[subcategory].select = true;
       dirtyCategories.push({ type: 'subcategory', subcategory, category });
     }
diff --git a/packages/ui-default/tool/checkTranslation.js b/packages/ui-default/tool/checkTranslation.js
index 5723d2979..5cd2844db 100644
--- a/packages/ui-default/tool/checkTranslation.js
+++ b/packages/ui-default/tool/checkTranslation.js
@@ -25,8 +25,8 @@ function _(str, format) {
   if (!texts[str]) texts[str] = [currentFile];
   else texts[str].push(currentFile);
 }
-const i18n = _;
-const Setting = _;
+const i18n = _; // lgtm [js/unused-local-variable]
+const Setting = _; // lgtm [js/unused-local-variable]
 
 function scanTemplate(folder, relative = 'templates') {
   const files = fs.readdirSync(folder);
diff --git a/packages/utils/lib/utils.ts b/packages/utils/lib/utils.ts
index 9ca2f7dbc..79d734b37 100644
--- a/packages/utils/lib/utils.ts
+++ b/packages/utils/lib/utils.ts
@@ -1,4 +1,4 @@
-import path, { sep } from 'path';
+import path from 'path';
 import fs from 'fs-extra';
 import os from 'os';
 import { Duplex } from 'stream';