Of course it's not a 3.7.3 problem, it's a very well known bug of MSFS 2024 SU4 Beta that started with the Beta and doesn't happen in SU3 (or MSFS 2020).
Asobo has been notified of the problem and has logged in their bug list, since it's confirmed to be an SU4-specific bug, but there's no telling if the fix will make it in time for the SU4 release, or will be postponed for a future update.
The only thing sure, there's nothing we can do in GSX to fix it, because the main point of the bug, is that tooltip messages are ignoring the size and always display at the same fixed size, that's what the bug is about.
