I'm marking this critical as I can't make a fix to 5.13 blead until this is changed. Attached is a patch for this bug (as well as an attachment of the whole file, changed which you can just discard). The problem is that test 2.3.3 in utf8strict.t is looking at what is now a Unicode noncharacter, and so fails. The test came fromThat web page has been updated to change the test, and this patch merely changes the test to correspond to the updated web page, plus add a comment that would have helped me figure out what was going on sooner.
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