> Uh. Linux users would like a word here.

As a Linux user, I disagree. It's not quite the same. Yes, I could recompile my kernel if I wanted to. I can recompile most of userspace too. But it's a hassle, especially if you want to diverge from upstream, and maintain that divergence on a long-term basis.

You can do some fun hacks with LD_PRELOAD et al, but it's nowhere near the degree of flexibility and ease of access of browser extensions.

I am allowed to modify all the software as I see fit (and that's excellent), but the friction of actually doing so is (comparatively) high.