Huh. For every update/refresh/reload/hyperlink/etc of the tab Tor Browser automatically change a circuit when it was lost/broken/unresponsive/etc. But sometimes Tor Browser breaks (only secure?) connection to the site immediately (first bug) from the hyperlink, and this site was already opened for a long time in other tabs too, in this case (in log). And no refresh/F5/"Try Again" button can help (second bug), but any action in other tabs with this site triggers Tor Browser to make new connections and change the circuit until it finds a working one.
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