And it’s what makes Firefox Great (xul?), without it FF is nothing, without it there is no reason for me to continue using Firefox.
I really hope there will be a fork that continues to support the ‘Legacy’ extensions I use, especially classic theme restorer, EasyCopy, ImageZoom, NukeAnything Enhanced, Saved Password Editor, and a dozen more.
Either 57 supports my extensions or I cease support for firefox, there’s no 2 ways about it, I expect a large % of the userbase will also leave. Moz’ is crazy, it couldn’t of done a better job of committing suicide if it tried.