Fixed session persistence — extension now stays logged in after
Firefox restarts without requiring cache clearing.

This extension uses innerHTML for rendering UI components. All content
inserted via innerHTML is generated entirely from internal state and
hardcoded strings — no user input or external data is ever inserted
directly into innerHTML. The only dynamic values injected are:
- Numbers (totalCount, dates)
- Strings from Supabase (habit titles) which are text-only display names

No external URLs, scripts, or untrusted content are ever rendered.
The extension has no remote code execution. All logic is in newtab.js
which is a local file bundled with the extension.