Why would ANYONE think changing the default printer setting based on which printer you just used was a good idea? Fortunately, there’s a way to turn that off.
The newest version of Windows 10 allows Windows to ‘manage’ the default printer by changing automatically to the most recently used printer. To disable that, press the Windows key, click on ‘Settings’, [then ‘Devices’,] and under ‘Printers & scanners’, scroll down to ‘Let Windows manage my default printer’ and turn that feature off.
I swear they sit around at Microsoft with nothing better to do than dream up new ways to fuck over users. This doesn’t work for me at all; I have five printers hooked up to this machine and I definitely DON’T want the default changing just because I have to print a label or a large format document.
This goes clear back to 2015. I don’t know why it didn’t affect me until after the last major update.