Channel configuration {2,2} not shown in Logic

I noticed this while being sloppy with a plugin and setting the Projucer Plugin Channel Configuration to stereo-only {2,2} to avoid testing for various configurations.

The plugin will not show up in Logic on a stereo-in stereo-out although it passes validation. (And of course not on any other channel type either).

In Reaper the AU shows up as 2 in, 2 out as expected.

If I remove {2,2} from Projucer it shows up in Logic.

Any ideas why that is?

Logic 10.5.1
MacOS 10.14.6

Logic channel configurations can be awkward to test. Did you definitely force all cached information about the plugin to be completely invalidated? In the past I’ve needed to change the plugin code in order for Logic to recognise the plugin as “new” and re-test the plugin’s supported channel configurations.

Yeah, I even restarted and all that.
So to be more clear, I see the plugin in the Plugin Manager / AU-validation, where it initially crashed. Then after adding {2,2} it passed validation. But still not showing for any channel type I can come up with.

Adding to this, nudging the plugin code and recompiling I suddenly got two instances of the same plugin in Logic: Plugin Manager although there’s only a single component file (in home folder and no duplicate in root) so there seems to be some caching issue.

Also it’s strange because in Plugin Manager the right-click remove option never seems to work. It’s always greyed out.

Anyway I finally got one single working version of the plugin and the Channel Configuration option also kicked in correctly. However I find this all very confusing, it seems to me the Plugin Manager in Logic is not really working properly. Seems to me logging out/in then starting Logic is doing the real AU-scan. Because when I do this Logic takes a lot more time to start the first time after logging in. Like it’s scanning something.