Stack Overflow Indentation++ v0.2
An Add-on that enables rich IDE-like tabbing and tab-shifting when editing questions/answers in Stack Overflow and Meta Stack Overflow.
It uses spaces (not tab characters) when you tab, and defaults to 4 spaces. It also adds a pretty gradient border to the text area.
Click on the extension in your toolbar to open up the settings, where you can change the spaces-per-tab, disable the border gradient, and disable the whole extension temporarily if you'd like.
Check out this project on GitHub to view the source code or read the README with more context on why I created this!