I built diffy, a browser extension that improves GitHub PR review experience and even works on large PRs. It gives you a full-screen scrollable diff with a searchable file tree, side-by-side and unified view, 50+ themes, inline comments, and review workflow. All of this in <2MB.

Try it (no account needed) Chrome (https://chromewebstore.google.com/detail/diffy/oaakiockkfndn...) and Firefox (https://addons.mozilla.org/en-US/firefox/addon/diffy-pr/)

- On any PR page -> click View Diff

- Anywhere on GitHub -> right-click a PR link -> Open in diffy

Works on public repos out of the box. A GitHub token is only needed for private repos, higher API rate limits, posting comments and review workflow.

How diffy works?

On a PR page it adds a View Diff button and starts prefetching the PR in the background. You can also right-click any PR link → Open in diffy.

When you open a PR, diffy fetches the diff through the GitHub API and shows it in a full-screen overlay.

Tech: TypeScript, React, WXT, Pierre Trees and Diffs.

Questions, feedback - all welcome!