> demonstrate improvements in the important metrics that users care about

And yet market share is plummeting, doesn't that indicated that your metrics for what users care about are completely wrong?

It's hardly me alone having this experience, most firefox users had there extensions break for no visible benefit. Anyone with the non-default ubuntu theme has the same issue with text boxes, which indicates a complete lack of QA.

I also have a 15 year long emotional attachment to firefox and a desire to see it succeed, if you can't convince me these changes are for the better then good luck with the rest of the world.