Airmail for Business

When I try to move the main window to my extended monitor, it automatically moves back to my main window. I can open a message in a new window and move it to my extended monitor but not the main window. Why is that?!

I want nothing more than Airmail for Business, or an app like it, to succeed; a desktop mail app that works with multiple mail services and app services and, most importantly, does not store or collect our data or charge a subscription. "Why not use Apple Mail?" Cause Apple Mail's desktop UX is terrible. But man... Airmail's scroll and refresh bugs make it nearly unusuable. If you use naught but an apple trackpad (or, I presume, a magic mouse). But if you, like me, need to use other input devices for ergonomic reasons, you'll find that scrolling the mail list will often completely (and invisibly) lock up a portion of the app. You can still open email and you can still scroll with a trackpad or by grabbing the scroll handle, but your mouse wheel is kaput. On top of that, once it's in this state, it stops refreshing new email on the list. Restarting the app fixes this, but I effectively end up restarting the app nearly every time I tab over to it. It's so close and has the potential to be so good, but with just two updates in the past year, I'm dubious this will ever be resolved.

Purchased “business” version based on the functionality described in the App Store, only to find: 1. It does not in fact sync to iOS calendar, just opens a blank appointment and you have to manually re-enter all the info, 2. It does not in fact support HTML rich content in either the message body or an email signature, 3. It does not work on a device without an M1 processor, so my Mac is out-of-luck and the program therefore will not integrate across all my devices. Apparently Airmail Pro does in fact support the advertised functionality, but of course it’s a monthly subscription to use their servers for data storage (which pretty much nobody needs) instead of a one-time purchase. Now I have one product that I already paid for except doesn’t do what it said it would, and if I want what I thought I was buying I have to switch over to Pro and pay twice for it.