[snitko]

A slightly offtopic question: can anybody point me to a js lib, which converted tabs pressed when inside a textarea into spaces and indented the text below accordingly?

[jkimbo]

http://jakiestfu.github.io/Behave.js/ is a bit more of a lightweight option than a full code editor.

[jakebellacera]

This is great, I've been looking for something like this. Thanks!

[terabytest]

http://ace.c9.io/ is probably what you're looking for.

[Ralfp]

Ace Editor is pretty comfigurable and allows for this as well as syntax highlighting for, say, markdown.