"Upgrade Available" causes significant slowdown (Linux and low-end machine)

[Sarke]

Screenshots were taken right before and right after one upgrade became available. No items were placed or changed between screenshots. The slowdown persists until the upgrade is made and the notification goes away.

I'm not sure if it's the star animation that causes it, or some other background check related to the upgrades, but it's definitely something related to the notification.

[Sarke]

Now that I think about it, there's also a similar slowdown when the game is saved. I attributed it to just processing needed for the save, but it might just be the diskette icon animation...

Perhaps an option in the Performance settings to disable icon animations could be beneficial?

[Sarke]

Maybe related to #1471?