If your Plasma desktop forgets its DPI, here's a solution

This is probably my weirdest tutorial yet. Indeed, a guide on how to work around an obscure issue of selective DPI scale factor reset for Dolphin and certain other apps following reboot in the Plasma desktop environment on devices with Nvidia or hybrid graphics setups, including overview of the problem, monitoring configuration files for changes, manual fix using the touch command in a Plasma session login script, and more. Take a look.