While I also miss some of the capabilities, I also can understand why Firefox removed them. Extensions systems which don't have very clear cut boundaries like

While I also miss some of the capabilities, I also can understand why Firefox removed them. Extensions systems which don't have very clear cut boundaries like XUL are just add a very hefty maintenance burden and make review extremely hard. It's not really about "normies". This doesn't really apply to the current change, as extensions already have clear boundaries and and as the article pointed out problematic apps likely won't be too much affected as they often already do things which bypass the constraints to avoid detection by the reviewer... (assuming I understand the topic correctly)