But why? There’s no need for a PDF editor in a browser. This is just raising the size and lowering the performance of a browser for a feature that almost no one needs or wants.
Mozilla should probably build a PDF viewer/editor (Adobe sucks and Foxit has gone downhill in recent years), but it’s not part of Firefox.
We’re (US) is in a growth cycle. This is a common thing – the companies need to try to keep up with growth/markets, so squeeze people for more money. Reddit is doing it – trying to IPO. Red Hat is doing it with this, though for me they’ve never been compelling or useful – I’m shocked they’ve hung on this long. Their products in my (very limited) experience are mediocre.
It has nothing to do with website design. It’s part of the HTTP protocol. A poor part in today’s understanding and use cases, but in the 90s it would have made sense.