You cannot update Joomla 3.10.2 to a higher minor version when running PHP 8.1, or update extensions, due to a bug in file /libraries/src/Table/Table.php and/or /libraries/src/Table/Extension.php. This might apply to other Joomla 3.10.x minor versions, but is fixed with Joomla 3.10.11 or before. A temporary fix to allow upgrading to Joomla 3.10.11:

$ sudo vim /libraries/src/Table/Table.php
line 180: $fields = $this->getFields(); --> $fields = $this->getFields(true);

Update Joomla to version 3.10.11, after which the site works correctly again.

Update packages for Joomla 3.10.11