Free Flight page - time slider quirk

There seems to be a quirk with the time slider on the flight setup screen? Sometimes it’s a solid blue bar (as in the pic), other times there’s a thin red vertical bar you have to slide. Both are quite tricky to grab/manipulate, more so the thin red bar.

I’ve no idea why this varies. It seems completely random, unless I’m missing something.

Currently on msfs-2024 but I’m sure the same used to happen in 2020.

The only time I remember seeing the thin red line is when I’ve got “live time” and “live weather” set. Then it will change colors when I try to move the slider back to “historical weather” when I change time. Different screen than the one you’re showing, but I’m on PC if that makes any difference.
Regards