Filling a cell with text in Calc

I have a column filled with values like “20y”. If, in a cell below such an entry, I enter “20” it displays “202”. If I then press Enter it displays “20y” correctly. In a previous version after entering “20” it would have displayed “20y” with the “y” highlighted (assuming in both cases there was no other entry starting with “20”).
It works properly in Safe Mode but creating a new user profile didn’t fix the problem. I’m using version 25.2.4.3

works for me in that version Flatpak in Linux (Debian).
Is the column format set to text or number?