Agreed with most of this stuff, but search on / (and even ctrl-f on some websites!) is horrible because it overrides the browser's shortcuts. When I press / I expect the Firefox quick find bar to come up, complete with highlighting and markers in the scrollbar and ctrl-{shift}-g to move between results and esc to exit search. Not some half baked JS search implementation or an unrelated search like in this extension - it searches for wiki pages, not text within the current page.

Fortunately this is pretty simple to disable with Greasemonkey (also 's' on github, though the userscript doesn't seem to work on Gitlab...).