Steps to reproduce:
1. Open the “user’s attached project”
2. Open “SampleScene”
3. Make some changes to the project
4. Enter Play Mode
5. Repeatedly press command + S to save while Play Mode is loading
6. Observe the crash

Reproducible with versions: 6000.0.34f1, 6000.0.37f1, 6000.0.48f1
Not reproducible with versions: 2021.3.51f1, 2022.3.61f1, 6000.0.36f1, 6000.1.1f1, 6000.2.0a10
Fixed in versions: 6000.0.35f1

Reproducible on: macOS 15.3.2 (M1 Max)
Not reproducible on: no other environment tested

First few lines of StackTrace:

{noformat}#0 0x00000195f28fd4 in -[NSApplication endModalSession:]
#1 0x00000107c43cb4 in -[ProgressbarController hideWindow]
#2 0x00000107c44758 in -[ProgressbarNotificationHandler handleClearNotification:]
#3 0x00000192135370 in __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__
#4 0x000001921c620c in ___CFXRegistrationPost_block_invoke{noformat}