This morning I finish the research on issue #9561(Nighty Five Sixty One), which complains that within the org unit user list table, when a column contains a very long value, it becomes too close to the next column in mobile view. This afternoon I have finished fixing and as mentioned by Kacper and Michal, I should try to avoid any side effect introduced by this CSS change. So I will do manual test tomorrow, and probably I will pick another new issue.