[Endy]

Mozilla was also committed to a good browser experience that looked and felt like something that was not Chrome or Safari. Then Australis happened. And Mozilla was committed to XUL. Then WebExtensions happened. Mozilla is committed to Gecko today. Tomorrow, Blink/Chromium will happen.

[dblohm7]

I'd suggest that you read my colleague's comment at https://news.ycombinator.com/item?id=15696184 to understand just how much friction the legacy addon ecosystem was creating. It just wasn't sustainable.

[Endy]

As a user of some of those "legacy" addons, I sincerely don't care about the upstream friction. I care that Mozilla has tried to cut my user experience off at the ankles more than once. The burden of having a thriving community & ecosystem is the responsibility of stewardship over that ecosystem. Mozilla has abrogated that implicit stewardship responsibility toward their community.