I happened similar case, and fixed with this way:
https://developer.apple.com/forums/thread/132890?answerId=616133022#616133022
It buggy about Web Inspector in Mac-Safari 13.
I suggest try to use Mac-Safari 14 by Technology preview if you want.
mf-yashims85
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Maybe same issue: https://developer.apple.com/forums/thread/132890?answerId=616133022#616133022
Fix way same it.
It buggy about Web Inspector in Mac-Safari 13.
I suggest try to use Mac-Safari 14 by Technology preview if you want.