I've always found that behavior baffling so it's interesting to hear someone using it as intended instead of being frustrated by it.

This is my biggest gripe with modern browsers. Stop fucking with my keyboard. I want my keyboard to control my agent, not some script. No key seems to be safe. The quick-search key (/) is often overriden by "clever" web devs, but not even in a consistent way. Ctrl-K to go to the browser search box is gone. I use emacs keybindings in text boxes, but those can be randomly overriden by scripts (e.g. Ctrl-B might by overridden to make stuff "bold" etc.).

I want to be able to say "Don't let any script have access to these keyboard keys". But apparently that can't be done even with extensions. I've strongly considered forking Firefox to do this, but I know how much effort that would be to maintain.

How hard would it be to write scripts that expose an interface that the user can bind to keys themselves, if they wish to?

One more for the spacebar to advance the page. Have never encountered a broken site (so far). Fingers crossed.