Depends on the definition of "ported". If we mean no loss of features, than many many extensions won't be ported in time. All vertical tabs extensions for exam

Depends on the definition of "ported". If we mean no loss of features, than many many extensions won't be ported in time. All vertical tabs extensions for example. Every extension with a native context menu. Stuff like Fire Gestures, CTR, Beyond Australis, DownThemAll!, .... http://arewewebextensionsyet.com http://arewewebextensionsyet.com shows that still a lot of bug reports exist and even unported extensions. If you subtract the WebExtensions with missing functionality (even uBlock Origin isn't quite the same), you will see the most of the popular extensions are NOT ported. Also have a look at: http://fasezero.com/lastnotice.html http://fasezero.com/lastnotice.html