StashBridge

About

Web apps store your preferences, favorites, and UI state in
  localStorage. Switch browsers, clear your cache, or open a
  new device — and it's all gone. There's no native way to
  sync this across browsers.

  StashBridge is a browser extension that watches localStorage
   on sites you whitelist and syncs it across all your
  browsers.

  ZERO SETUP DEFAULT — Uses your browser's built-in sync
  (Chrome Sync, Brave Sync, Firefox Sync). Just install,
  whitelist sites, and go. No server needed.

  OPTIONAL SERVER RELAY — For cross-browser sync (Chrome to
  Firefox), connect a free Cloudflare Worker relay.

  FEATURES
  • Configurable origin whitelist — only sync the sites you
  choose
  • Per-key sync — granular key filtering or wildcard (sync
  all keys)
  • LZ-String compression — fits more data in the 100KB
  browser sync limit
  • Optional AES-256 encryption — encrypt data with a
  passphrase before syncing
  • Storage usage indicator — see how much of the sync quota
  you're using
  • Offline resilient — changes queue locally and push when
  connectivity returns
  • Dark glassmorphism UI — clean, minimal popup interface

  USE CASES
  • Sync favorited plugins on Obsidian Stats
  • Keep Hacker News upvoted/hidden stories across browsers
  • Sync preferences for dev tools (Swagger UI, GraphQL
  Playground)
  • Persist layout preferences for self-hosted dashboards
  • Any web app that stores state in localStorage but doesn't
  offer cloud sync

  COST: $0/month. Browser sync is free. The optional server
  relay runs on Cloudflare's free tier.

  PRIVACY: No data is collected or sent to the developer. All
  sync happens through your browser's built-in sync or a
  server you control. Open source at
  github.com/cybersader/stashbridge