fix: downgrade version to 1.5.4 and update save-hint class in popup.html

Author: zarkin404

extension/package-lock.json

@@ -81,7 +81,7 @@
     }
     .settings button:hover { background: #0066d6; }
     .settings button:active { opacity: 0.9; }
-    .save-hint {
+    .settings .save-hint {
       margin-top: 6px;
       font-size: 11px;
       color: #34c759;