Reproduction steps:
1. Create a project using the “Karting Microgame” template
2. Open the project

Expected result: The project opens
Actual result: Unity Editor crashes

Reproducible with: 2021.3.12f1

Reproducible on: Ubuntu 20.04.5

First lines of the stack trace:

{noformat}#0 0x0055d0e2596a7c in burst_signal_handler(int, siginfo_t*, void*)
#1 0x007f7bfb286420 in funlockfile
#2 0x0055d0e525d2fe in d_print_comp_inner
#3 0x0055d0e525e9c3 in d_print_comp
#4 0x0055d0e525d47b in d_print_comp_inner
#5 0x0055d0e525e9c3 in d_print_comp{noformat}

Or more interestingly (from Editor log):
Thread 1 (Thread 0x7f7bf824a380 (LWP 58762)):

{code:java}
#0 0x00007f7bfb162c7f in __GI___wait4 (pid=63940, stat_loc=0x7f7bac055f2c, options=0, usage=0x0) at ../sysdeps/unix/sysv/linux/wait4.c:27
#1 0x00007f7aec14229f in ?? () from /home/thomas/Unity/Hub/Editor/2021.3.12f1/Editor/Data/MonoBleedingEdge/MonoEmbedRuntime/libmonobdwgc-2.0.so
#2 0x00007f7aec0ead3d in ?? () from /home/thomas/Unity/Hub/Editor/2021.3.12f1/Editor/Data/MonoBleedingEdge/MonoEmbedRuntime/libmonobdwgc-2.0.so
#3 0x00007f7aec070095 in ?? () from /home/thomas/Unity/Hub/Editor/2021.3.12f1/Editor/Data/MonoBleedingEdge/MonoEmbedRuntime/libmonobdwgc-2.0.so
#4 0x000055d0e25969cc in burst_signal_handler(int, siginfo_t*, void*) ()
#5 <signal handler called>
#6 0x000055d0e45745ed in video_YUV420_convert::DecodeYUVFrame(video_YUV420_convert::RGBYUVInfo*, ImageReference*) ()
#7 0x000055d0e3357cc7 in VP8VideoMedia::GetNextVideoFrame(ImageReference*, VideoClipMedia::VideoFrameInfo*) ()
#8 0x000055d0e355ddbb in VideoClipTranscode::SetToDefault(VideoClipTranscode::TranscodeInfo const&, VideoMedia&, VideoClipTranscode::ClipInfo*, bool) ()
#9 0x000055d0e355e100 in VideoClipTranscode::Import(VideoMedia&, core::basic_string<char, core::StringStorageDefault<char> > const&, core::basic_string<char, core::StringStorageDefault<char> > const&, VideoClipTranscode::TranscodeInfo const&, VideoClipTranscode::ClipInfo*, void (*)(float, core::basic_string_ref<char>, bool), AssetImporter*) ()
#10 0x000055d0e3ffdfca in VideoClipImporter::GenerateAssetData(AssetImportContext&) ()
#11 0x000055d0e3eabed9 in ImportToObjects(core::basic_string<char, core::StringStorageDefault<char> > const&, core::hash_map<AssetDatabase::ImporterID, ImporterInfo, core::hash<AssetDatabase::ImporterID>, std::equal_to<AssetDatabase::ImporterID> > const&, dynamic_array<PostprocessorInfo, 0ul> const&, AssetResolveTracker const&, ImportAssetInputs const&, ImportAssetOutputs&, IImportProgress*) ()
#12 0x000055d0e3eaae7e in ImportAsset(core::hash_map<AssetDatabase::ImporterID, ImporterInfo, core::hash<AssetDatabase::ImporterID>, std::equal_to<AssetDatabase::ImporterID> > const&, dynamic_array<PostprocessorInfo, 0ul> const&, AssetResolveTracker const&, ImportAssetInputs const&, ImportAssetOutputs&, IImportProgress*) ()
#13 0x000055d0e3ed55ef in AssetImportWorker::Import(AssetResolver&, WorkerImportPayload const&, WorkerImportResponse&, IImportProgress*, bool*) ()
#14 0x000055d0e3f1a458 in AssetImportManager::ImportInProcess(AssetResolver&, ArtifactKey const&, AssetImportParameters const&, AssetDatabase::ArtifactID&, IImportProgress*, core::hash_set<core::basic_string<char, core::StringStorageDefault<char> >, core::hash<core::basic_string<char, core::StringStorageDefault<char> > >, std::equal_to<core::basic_string<char, core::StringStorageDefault<char> > > >&, CrashedAssetImportsDatabase&) ()
#15 0x000055d0e3f05f68 in AssetImportManager::Import(core::hash_map<AssetDatabase::ImporterID, ImporterInfo, core::hash<AssetDatabase::ImporterID>, std::equal_to<AssetDatabase::ImporterID> > const&, dynamic_array<PostprocessorInfo, 0ul> const&, AssetResolver&, CategorizedAssets&, IImportProgress*, core::hash_set<UnityGUID, core::hash<UnityGUID>, std::equal_to<UnityGUID> > const&, LoadedImportedAssetsSnapshot*, LoadedSourceAssetsSnapshot*, core::hash_set<core::basic_string<char, core::StringStorageDefault<char> >, core::hash<core::basic_string<char, core::StringStorageDefault<char> > >, std::equal_to<core::basic_string<char, core::StringStorageDefault<char> > > >&, CrashedAssetImportsDatabase&, OnDemandScheduler&) ()
#16 0x000055d0e3f2df60 in RefreshInternalV2(AssetDatabase::UpdateAssetOptions, ScanFilter const&, InternalRefreshFlagsV2) ()
#17 0x000055d0e3f0855d in StopAssetImportingV2Internal(AssetDatabase::UpdateAssetOptions, InternalRefreshFlagsV2, ScanFilter const*, char const*) ()
#18 0x000055d0e3f0ac69 in InitialRefreshV2(bool) ()
#19 0x000055d0e3abfc67 in Application::InitializeProject() ()
#20 0x000055d0e3b68ffd in InitializeUnity(void*) ()
#21 0x00007f7bfb7afbe8 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#22 0x00007f7bfb7af04e in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#23 0x00007f7bfb7af400 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#24 0x00007f7bfb7af6f3 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#25 0x00007f7bfbe4412d in gtk_main () from /lib/x86_64-linux-gnu/libgtk-3.so.0
#26 0x000055d0e3b68787 in main ()
{code}