ErrorException: [E_WARNING] Undefined array key "sessionActivityOptimized"

[rdn]

Error happens during web upgrade from 2.2.7 to 2.2.8, but only once.
Using PHP 8.0.13

PHP:

Server error log
ErrorException: [E_WARNING] Undefined array key "sessionActivityOptimized" src/XF/Repository/SessionActivity.php:125
Generated by: Unknown account Dec 3, 2021 at 4:25 AM

Stack trace
#0 src/XF/Repository/SessionActivity.php(125): XF::handlePhpError(2, '[E_WARNING] Und...', '/home/nginx/dom...', 125)
#1 src/XF/Pub/Controller/AbstractController.php(84)...

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