Quote Originally Posted by Jonax View Post
I for one never encountered this scaling before. As you say the Lazarus forum is very helpful.

I guess most Raspberry users don't use High DPI monitor. And frankly I don't either.
You probably never encountered this because you don't own High DPI monitor so Windows never went into this as they call legacy scaling mode which completely breaks some applications. And yes this can even break some of older Microsoft applications.
There is a reason why Windows 10 and Windows 11 are actually logging which DPI scaling their users use for certain applications (yes on modern Windows versions user can force specific application to use one of the four scalling methods) so that when a user installs some old application Windows can check Microsoft database to see if Microsoft already has some information about which Scaling type most users use.

Quote Originally Posted by Jonax View Post
MyIntegerVariableForScaling := Screen.PixelsPerInch;
Yeah this will work for as long as Windows report correct DPI resolution. But for this your application manifest file must contain proper entries to tel Windows that it does support High DPI scaling. Without that Windows will report wrong DPI resolution.

Any way I also don't have High DPI monitor so I don't have actual experience with this but I did read several questions and their respective answers about this topic on Stack Overflow.
Well technically I do have High DPI screen if I connect my computer to Smart TV that I got for free from my friend.

And no I don't have some rich friends. This is just about six or seven years old Smart TV whole back-light electronics has gone bad so now I can be happy if screen remains constantly lit for 10 minutes otherwise it keeps turning black after about one to two minutes and remains black for about half a minute each time. Replacing back-light electronics would cost about 120 EUR which is half of the price of some cheaper Smart TV-s out there. So now I'm kinda hoping that someone else might donate me similar or same model so I can try and use parts from both to make at leas one working