The entire Android app was overhauled a while back, dropping functionally and decreasing stability, and has since been pretty much ignored even though it is still missing features and is still painfully clunky and prone to crash. The developer tools on the desktop app were ahead of Chrome but have stagnated, and they're slow to adopt new standards, but they somehow find time to add things no one asked for like Colorways and a VPN.
I want Firefox to get its traction back, but it's hard to cheer for Mozilla or blame Google when I see them twiddling their thumbs like this.