After adding the new product "TF3680 - TC3 Filter" as a reference, some new files were automatically generated after compilation:
_ModuleInstall/TcFilter/TwinCAT CE7 (ARMV7)/TcFilterW32.dll
_ModuleInstall/TcFilter/TwinCAT CE7 (x86)/TcFilterW32.dll
_ModuleInstall/TcFilter/TwinCAT RT (x64)/TcFilter.sys
_ModuleInstall/TcFilter/TwinCAT RT (x86)/TcFilter.sys
After contacting Beckhoff support, it was concluded that the folder "_ModuleInstall" could be omitted from version control, thus this addition.
As a product of enabling the write of separate LineIDs (described here https://github.com/tcunit/TcUnit/issues/85) and having a discussion with Beckhoff support, it was concluded that the files "LineIDs.dbg" and "LineIDs.dbg.bak" should not be version controlled, and thus these two are added to the gitignore-file for TwinCAT3.
Renamed TwinCAT.gitignore to TwinCAT3.gitignore so it's obvious this is a gitignore file only applicable for TwinCAT3 and not also TwinCAT2 (which stores everything in a big binary blob).