I would agree with you normally. But in this case there's a much bigger "bug" they must handle: The vast majority of users have migrated to Chrome or some other browser that don't respect their privacy.
We power users are like 1-2% of all FF users. I think it's acceptable to break some things for a while to bring back much more users than that.
In the mean time, they've lost one of those power users (likely more, going by some of the discussion in issues for various vim-like plugins) and will, in the future, need to do something to entice me back. This experience has left a bad taste in my mouth and I'm not going to be rushing to go back to a browser that breaks functionality on me without prompt.
They lost me once for terrible, terrible performance. For a year or two until I really needed tree style tabs back. They need to prioritize. Deal with it.
Also, since you're a power user, why don't you use that proposed API already? It seems you don't even need to compile the browser or anything, just enabling a flag and installing the API as an addon.
> They lost me once for terrible, terrible performance. For a year or two until I really needed tree style tabs back. They need to prioritize. Deal with it.
I am dealing with it. I moved to a different browser.
> Also, since you're a power user, why don't you use that proposed API already? It seems you don't even need to compile the browser or anything, just enabling a flag and installing the API as an addon.
We power users are like 1-2% of all FF users. I think it's acceptable to break some things for a while to bring back much more users than that.