w3m.vim VS firenvim

for leetcode specifically, i use firenvim to start a neovim session in the text area that would normally be leetcode's area and then have an autocmd that looks for "leetcode" in the filename and prompts me to select a filetype.

Yea worth it. As far as good for certain languages over others: text is text. Once you’re more experienced with how (neo)vim works, you won’t want to type anywhere. Like in the browser or obsidian

It's just the popular firenvim system: https://github.com/glacambre/firenvim

In that case give firenvim[1] a try. It uses your existing config (keymaps, plugins, autocmds, etc).

[1] https://github.com/glacambre/firenvim

You propably could use https://github.com/glacambre/firenvim inside of overleaf webpage. Althought I haven't tested it.

https://github.com/glacambre/firenvim is the correct link.

If by everywhere you mean everywhere, then take a look on this https://github.com/glacambre/firenvim

In general, for "rich text editors", firenvim needs to add special handling. For example firenvim supports CodeMirror (or used to): https://github.com/glacambre/firenvim/pull/623

> Can you make Firefox's form inputs use Vim keybindings?

Do you mean something like this: https://github.com/glacambre/firenvim?