TIA Revisions - JetSetIlly/Gopher2600-Docs GitHub Wiki
Gopher2600 supports common revisions in the TIA chip. The details of the TIA chip can be changed through the preferences window (in the VCS tab).
A summary of the known TIA revisions / bugs can be found int the Atari Compendium. Not all revisions / bugs are supported by Gopher2600 but the common ones are.