This IS a real problem, and no, having to set your secondary monitor as your "main" monitor is not an acceptable workaround. QuickBooks has always worked poorly with high-DPI displays, rendering some text normally and some very small--regardless of system or compatibility settings. For this problem, it's not just a matter of small, barely readable text. The popups that appear on the "main" monitor are very small, easily unnoticeable, and modal, so the application appears to "hang" until they're dismissed. Even worse, they occasionally pop up behind another application, so it's not obvious why QuickBooks has suddenly stopped responding.

For issues like this that negatively impact user experience, paying customers and subscribers have every right to expect Intuit to devote developer resources to fix them. Especially years after it first became a problem. Please! Do something.