Reproduction steps:
1. Open the attached “BugRepro” project
2. In the menu bar at the top of the Editor, select “ReimportAllVfx” > “ReimportAllVfx”
3. Wait while the reimporting is done

Expected result: The reimporting process is done successfully
Actual result: After a couple of minutes the Editor crashes

Reproducible with: 6000.0.11f1
Not reproducible with: 2021.3.41f1, 2022.3.39f1, 6000.0.10f1
Fixed in: 6000.0.12f1

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

Note: The time to crash varies

First few lines of the stack trace::
0x00007FFDE8137DD3 (Unity) ShaderVariantEnumerationKeywords::FindStaticKeywordTuples
0x00007FFDE813E568 (Unity) ShaderVariantEnumerationKeywords::PrepareEnumeration
0x00007FFDE8C8FC53 (Unity) ShaderSnippet::RebuildKeywordMasks
0x00007FFDE8C8E1BA (Unity) ShaderCompilationInfo::EndKeywordCombinations
0x00007FFDE80EDB53 (Unity) ShaderCompilerPreprocessCallbackImpl::OnEndKeywordCombinations
0x00007FFDE8684CB8 (Unity) ShaderCompilerPreprocess
0x00007FFDE80E48CB (Unity) DoShaderImportProcessing
0x00007FFDE80F218E (Unity) ShaderImporter::UpdateShaderWithSource
0x00007FFDE87741AD (Unity) VisualEffectImporter::GenerateAssetData