Happened on at least late October Version 130.0.2849.52 all the way up to the present 131.0.2903.86.
WP logout occurs on one tab but not another, and vice versa, login on one tab, still logged out on other. Typically this happens with the Dashboard in one tab as that loads with the www prefix to the url, the forums now tend to load without the offending www as specified in the permalinks. Also repro’d when logging out of www forums after which another tab with forums is still logged in.
As would be expected, the www is preserved after selecting another topic in the forums, as is a no www topic is preserved when selected from no www forum. YaknawwadImean. 😛
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