'Return to Menu' button Crash roblox client for everyone, everytime. [incl. repro, crashlog]

[PlaceRebuilder]

In my game when you spectate, you can click return to menu.
This has worked fine for about 3 years now, until about 12 hours ago when it started crashing roblox.

Here’s how it look:

This happens for everyone, every time you click the return button.
It also happens when players return to menu after playing a round, effectivly and completely killing my game.

I havn’t updated my game for days so I dont think it’s my code doing this.

Crashlog:

1571724930.08850,0d48,6 LoadClientSettingsFromLocal group: "ClientAppSettings"
1571724930.12050,0d48,6 Loading AppSettings.xml from C:\Users\MyComputer\AppData\Local\Roblox\Versions\version-8a3a5a93945b4365\AppSettings.xml
1571724930.12050,0d48,6 setAssetFolder content
1571724930.12150,0d48,6 CrashReporter Start
1571724930.12150,0d48,6 Info: Searching for and uploading crash dumps
1571724930.12150,09c0,6 WatcherThread Started

Gamelink: Empty Baseplate - Roblox

Repro:

1. Press play on my game (see gamelink).
2. Press singleplayer
3. Bottom-right button click Menu > Spectate
4. Click ‘Menu’ at top right.

I can send dmp file to staff on request (not sure what kind of sensitive information it contains so I can’t give to anyone).

EDIT: Appears like the bug has now been fixed.
I didn’t update my game but now things are working again.

[Automationeer (Eleanor)]

• Can you give a step-by-step list of what the script does on click?
• Is there any output errors? This can be caused by a stack overflow. Try clicking it in studio or with the F9 console open.

[PlaceRebuilder]

It crashes in studio too, but only the client side.
It’s when you return to menu that it crash.
All the Script does is remove previous ScreenGuis and add the Menu gui - the same menu gui you got when you first entered the game. And it didnt crash then so I would assume it’s not the menu gui causing the crash.

[Automationeer (Eleanor)]

Any loops as part of that process? eg loops that could be causing a stack overflow.

[mrow_pizza]

We’ve disabled the flag responsible for this. Sorry for the inconvenience!

[PlaceRebuilder]

Great, it works again now! Thanks!

[Automationeer (Eleanor)]

Out of curiosity, what was this change? Was it this?