Possible bug with soloing the grouped tracks

I'm using Logic Pro X version 10.4.6

I think I have found a bug with soloing the tracks that are grouped together. Maybe it was designed so intentionally, though it feels strange.

Here's the problem

Given:

- I have 8 tracks stacked in a "Summing stack" and then grouped,

- The check-box "Solo" in the settings of the group is unchecked.

- None of the tracks in the project are muted or soloed

Action:

- I try to solo any single track in the group

Outcome that I don't think is right:

- Logic soloes all the tracks in the group (though it doesn't show that they're solo but I can clearly hear them all).

Also, when I check the "Solo" check-box in the settings of the group and try to solo any track in the group Logic soloes them all and also shows it (as expected — works right).

Soloing works fine with Summing stacks that are not grouped.

And lastly, I have this problem in 11 projects organised the same way.