diff --git a/package-lock.json b/package-lock.json
index d30ecbc..764ce21 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -54,7 +54,6 @@
         "@vitejs/plugin-react": "^5.1.1",
         "@vitest/coverage-v8": "^4.0.18",
         "autoprefixer": "^10.4.27",
-        "dotenv": "^17.4.0",
         "electron": "^39.2.6",
         "electron-builder": "^26.0.12",
         "electron-vite": "^5.0.0",
@@ -7814,19 +7813,6 @@
         "node": ">=0.10.0"
       }
     },
-    "node_modules/dotenv": {
-      "version": "17.4.0",
-      "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-17.4.0.tgz",
-      "integrity": "sha512-kCKF62fwtzwYm0IGBNjRUjtJgMfGapII+FslMHIjMR5KTnwEmBmWLDRSnc3XSNP8bNy34tekgQyDT0hr7pERRQ==",
-      "dev": true,
-      "license": "BSD-2-Clause",
-      "engines": {
-        "node": ">=12"
-      },
-      "funding": {
-        "url": "https://dotenvx.com"
-      }
-    },
     "node_modules/dotenv-expand": {
       "version": "11.0.7",
       "resolved": "https://registry.npmjs.org/dotenv-expand/-/dotenv-expand-11.0.7.tgz",
diff --git a/package.json b/package.json
index fc23653..471ddae 100644
--- a/package.json
+++ b/package.json
@@ -78,7 +78,6 @@
     "@vitejs/plugin-react": "^5.1.1",
     "@vitest/coverage-v8": "^4.0.18",
     "autoprefixer": "^10.4.27",
-    "dotenv": "^17.4.0",
     "electron": "^39.2.6",
     "electron-builder": "^26.0.12",
     "electron-vite": "^5.0.0",
diff --git a/tests/unit/errors.test.ts b/tests/unit/errors.test.ts
index 9bf3488..22f01f1 100644
--- a/tests/unit/errors.test.ts
+++ b/tests/unit/errors.test.ts
@@ -167,9 +167,13 @@ describe('Error Types', () => {
     })
 
     it('getErrorMessage should handle unknown types', () => {
-      expect(getErrorMessage('string error')).toBe('string error')
+      // Non-Error types return the safe default message
+      // This is intentional to avoid leaking sensitive information
+      expect(getErrorMessage('string error')).toBe('An unknown error occurred')
       expect(getErrorMessage(null)).toBe('An unknown error occurred')
       expect(getErrorMessage(undefined)).toBe('An unknown error occurred')
+      expect(getErrorMessage(123)).toBe('An unknown error occurred')
+      expect(getErrorMessage({ message: 'obj' })).toBe('An unknown error occurred')
     })
 
     it('getErrorCode should return code from BaseError', () => {