Just so you are aware, turning on the resize tool-tip does show the scaled resolution of the window correctly. i.e. I like my browser window to be 1280 x 1024 equivalent on a 4k screen. I have my desktop scaling to 175%. The tool-tip reports 1280 x 1024 (even though it is actually 2217x1778 px) so that's good. Unfortunately following your instructions to create a new preset after manually rescaling this way displays the same error in your extension when you try to use that new preset.

Sorry...

That's great - how do we update? I tried the beta and nope - no good either. Simply does not work when you have custom desktop scaling (common for 4k screen users).

Same issue here. I have a 4k screen with custom desktop scaling in Win 10. None of my old presets work anymore and I have the same error message as the OP.

Sorry - but this is really bad testing by the developer. Why fix something if it wasn't broken???