I'm running macOS 27 Golden Gate beta and since the first beta, Keyboard Maestro is always in the dock as "Running in Background". MacOS does not give an ignore option only a 'Stop Running in Background' option in context menu. This is due to a change where the system is trying to show users when apps are sneakily running after being quit. (MacObserver, 9to5Mac)
I use KM as a background tool I don't want in the Dock. Other apps on my system run in the background and don't get forced into the dock like KM is currently.
So is there any way to ignore/hide this that I can do as a user? Hopefully team will fix this when macOS 27 officially releases.
I probably shouldn't try to speak for Peter, but I think it's safe to say that he himself doesn't provide support for Beta OSs. But you are still welcome to post your questions here! There have been cases where new macOS features, for official OS releases (especially security features, not unlike the one you are talking about) have broken some KM actions. But I think once the official release arrives, patches to KM would come quickly, if needed. MacOS 27 is widely expected in September, regardless of whether any new Macs are released during that month. So you have another month to wait. Besides, it might not even be a problem when macOS 27 arrives.
I have not seen this myself when using the betas; Keyboard Maestro works like it does in prior releases. I don't know why you're seeing it and I'm not, so hopefully enough people see and report the issue such that Peter can investigate and determine if it's solvable or not.
I'm afraid it's not up to me to decide what Apple does or doesn't show in the Dock, and as noted I generally don't run betas, not unless I hear of significant issues, then I might try them on my test Mac. But this sounds more like a "feature" (as far as Apple is concerned), than a bug.
Though why you are getting different results to @griffman, that I could not speculate on.