Done:
- Compatibility checking on upgrade is in review
- New list view is nearly complete, waiting on details from UX
- New appearance view is nearly complete, waiting on details from UX
- New overall styling for all platforms is nearly complete, waiting on details from UX
- Made themes auto-enable on install from webpages
Next:
- Outdated plugin warnings
- Make add-on upgrades more fault tolerant
- Fix up the old patches for session history and download manager support
- Migrate pending installs from the old add-ons manager