This problem is extremely rare although a few users on other phpBB forum software sites have also experienced it however we never found an already published solution.
I was one of the few people experiencing this problem and, a few days ago, completely uninstalled a password manager (Dashlane) from my main computer. This fixed some things. I then completely removed and then re-installed Google Chrome. I then used my Chrome account to re-import my settings, extensions, bookmarks etc and everything seems to be working fine now.
This morning I re-installed Dashlane and everything seems to be okay still.
Apologies to anyone who has experienced the above. It's certainly a tremendously frustrating bug to experience.
Please let us know if you have experienced any of these problems.
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