Unable to find the Culprit using CL and Findit.
Using Code Search for the file, "HTMLParserIdioms.cpp" assigning to the concern owner.
Suspecting Commit#7dc7c0fc073b84f3050726b52ceec1bbcb304ba3
Suspecting Review URL# https://codereview.chromium.org/2058613002

@esprehn -- Could you please look into the issue, pardon me if it has nothing to do with your changes and if possible assign it to concern owner.
Thank You.

ClusterFuzz has detected this issue as fixed in range 428862:429212.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=5928585955377152

Fuzzer: libfuzzer_radamsa_text_resource_decoder_fuzzer
Job Type: libfuzzer_chrome_asan
Platform Id: linux

Crash Type: UNKNOWN READ
Crash Address: 0x000000000018
Crash State:
  get
  blink::threadSafeMatch
  blink::HTMLTokenizer::updateStateFor
  
Regressed: https://cluster-fuzz.appspot.com/revisions?job=libfuzzer_chrome_asan&range=423381:423433
Fixed: https://cluster-fuzz.appspot.com/revisions?job=libfuzzer_chrome_asan&range=428862:429212

Minimized Testcase (8.93 Kb): https://cluster-fuzz.appspot.com/download/AMIfv96mRrkVCCkVRhMUb07ZNR2ZZG540ULN3Dc8SMlt0QJAn9L9J5iOWtoH4cWXZmzClqcLO_zeKNtqbXUYHhu3G5pRyMYByKVBI4QQFzEK2PcfNKx_vyo53nWqGGM2QQKrzVWHz8oPg5-rb_9mHTb8IkLEBEcjkA?testcase_id=5928585955377152

See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reproducing.md for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase is verified as fixed, closing issue.

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