Distinguish by window class
It would be nice to distinguish windows by class. For example, the mintty terminal has a command-line option to set the class (e.g. to distinguish between local shells and ssh sessions). But WindowTabs still treats all as one application "mintty".
I (the requester) found a workaround: Copied mintty.exe to mintty-gShells.exe, mintty-gRemote.exe, etc. Now WindowTabs treats them as different programs. (And luckily, mintty's new window shortcut (Alt+F2) starts the same executable as the one i'm currently working in.)
I'd prefer hard links to copies (so updates to mintty.exe would update all), but they are not sufficient.
With the workaround, this feature's priority dropped to "nice to have" (just to avoid having to re-copy after each mintty update).
BTW, concerning your question: By now i'd use it (or rather am using the workaround) for both - mostly to have different auto-groups, but also to leave other instances ungrouped (e.g. scheduled tasks using the original mintty.exe with no grouping).
I'd use it for autogrouping per class.
Just looking to understand why it would be useful to identify the different classes of mintty - would you only add tabs to certain classes while leaving other classes untabbed? Or is it to allow autogrouping per class?