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The forums are working fine for me in Safari both on macOS and iOS. Did you maybe install a new extension or something that is causing a conflict?
 
Just as a test, can you make second (temp/test) account on your Mac and see if the issue still occurs in that account.

I've got to think it is something specific to your setup otherwise I would think we would be bombarded by complaints by now. 🙂
 
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