Yes, as I mentioned in my previous comment, a release was in the queue already and awaiting Google's moderation. It got approved and that's the version you have right now.

The fix will be in the next release - probably coming up within a few days.

Good catch! Of course, it was a CSS conflict but this time, caused by the 3rd party vendor I'm using called Popper Tooltip.

There's currently a pending release awaiting Google's moderation (and God knows how long it can take!), so this fix will be available in the following release.

Fixed for the next release - which is pending approval by Google (might take a couple of days!)

I have changed the icon to use a pushpin instead.
The proposed label would be too long for the size of the popup - so I will just use "Pin/Unpin as default"
Clearing the default is as easy as "unpinning" it, or pinning another one.

It will be available in the next release!

The little pop-up menu available for each segment will show an option to set a single Segment as the default one (replacing the "All Users" one). This will be set on a per-property basis.

I have also improved the handling of the "clear segments".

Done! It will be there in the next release.