Reproduction steps:
1. Open the attached “IN-92098” project
2. Navigate to Window > TextMeshPro > Font Asset Creator
3. Change the Source Font to “Bangers”
4. Click “Generate Font Atlas”
5. Observe the crash

Reproducible with: 6000.0.19f1, 6000.0.32f1, 6000.1.0b1
Not reproducible with: 2021.3.47f1, 2022.3.55f1, 6000.0.18f1

Reproducible on: Windows 11
Not reproducible on: No other environment tested

First few lines of the stack trace:
0x00007FFC54CC3469 (Unity) tlsf_free
0x00007FFC527F0C00 (Unity) DynamicHeapAllocator::Deallocate
0x00007FFC527FE945 (Unity) DelayedPointerDeletionManager::CleanupPendingMainThreadPointersInternal
0x00007FFC527FE11B (Unity) DualThreadAllocator<DynamicHeapAllocator>::Allocate
0x00007FFC527EF86D (Unity) MemoryManager::Allocate
0x00007FFC527FA21E (Unity) malloc_internal