6 months ago - AndrewT - Direct link
Pleaase start a new test galaxy with all mods disabled - do you still get this?  
6 months ago - AndrewT - Direct link
Please opt into the beta of the next patch

[DEV TEAM] 3.10.2 "Pyxis" Steam Open Beta

Hello! We've just released an update to the Stellaris Test branch on Steam, containing the 3.10.2 patch that is currently in certification for release later this week. Of particular note, this release includes a fix to a common MacOS crash (that... forum.paradoxplaza.com forum.paradoxplaza.com
THEN
Right-click on stellaris.exe, properties, compatibility. Tick "disable fullscreen optimizations" untick every other box in that dialog, Apply, and exit.
Then in the launcher Game Settings menu, select the fullScreen display mode, Vsync off, refresh rate 60.

And start another new galaxy. Is that any better?