See https://wpt.fyi/results/html/semantics/scripting-1/the-script-element/moving-between-documents?label=master&product=safari%5Bstable%5D&product=safari%5Bexperimental%5D&aligned&view=subtest&diff&filter=ADC&q=is%3Adifferent
<rdar://problem/98509821>
This is not a regression (probably it was flaky failure existing before). https://wpt.fyi/results/html/semantics/scripting-1/the-script-element/moving-between-documents?run_id=5206959209316352&run_id=5148886218309632
Why close this as WORKSFORME? I mean, we _shouldn't_ be flakily failing the test, even if I misdiagnosed what had happened in filing the issue.