To reproduce:
- Open Crash Repro.rbxl with Output open
- Get or upload a Mesh
- Replace the asset ID in the Script with that Mesh’s ID
- Press Play while in Test mode
- Observe the first :SetPosition call update the mesh
- Switch to Server (toggle button or switch tabs)
- Observe the crash after :SetPosition is called again
There’s a script under a MeshPart which creates an EditableMesh and applies it to the MeshPart. It then sets the position of the first vertex once, then again 3 seconds later.
Logs and problem report attached in private message. The logs include my Beta Features and the problem report has my system information, but I’m running macOS Sequoia 15.7.7 on an M1 Mac mini.
For a quick reference, last logs for one crash:
2026-10-02T16:45:31.478Z,207.478394,6cbe7000,6,Info [FLog::CreatorOutput] Moved vertex
2026-10-02T16:45:31.478Z,207.478455,6cbe7000,6,Info [FLog::CreatorOutput] Moving vertex again in 3 seconds
2026-10-02T16:45:31.479Z,207.479080,f4e422c0,6 [LOGCHANNELS + 1] RBXCRASH: DM Lock Violation (read the above comments for details)
And the top of the trace:
0 RobloxStudio 0x1087f8ee8 0x1047f4000 + 67129064
1 RobloxStudio 0x1089b3ae4 0x1047f4000 + 68942564
2 RobloxStudio 0x10972ae44 0x1047f4000 + 83062340
Notes
The script uses the ID of this Mesh which I set to Open Use but because of (I presume) some bug with Roblox’s asset system, it’s not actually Open Use and it errors.
This ONLY happens with Test/Test Here, not Server & Clients or Run. Team Test’s Server view doesn’t work so can’t test with that.
For whatever reason, the client doesn’t properly load the mesh - this might be related, I’m really not sure.
When the mesh does load on the client (in a published experience), it hasn’t crashed on the Client view but still crashed on Server.
A private message is associated with this bug report