I try to solve some caching issues I have with TBB. On websites which have hundreds of times the same image, TBB insists on re-downloading the image for every occurrence on the page even though the server correctly sets "expires", "max-age" and "cache control" headers. It does seem to respect the ETAGS and only gets a 304, but it still takes about 3 minutes to load a page like this.
I was looking to disable certain caching changes that might cause this but couldn't really find a reference for all the extensions.torbutton.xxx settings.
I only found this design documentation from 2011, but that seems outdated.