Odd window behavior...or is it me?

Hi everyone. I’m trying to figure out if what is happening is something to do with TB or something I’m doing wrong in Catalina, which does have some oddities.

I have my 13 inch MBPro that I take everywhere with me, but at home I have it hooked up to a large LG external monitor. I put my TB windows all on the external monitor, but when I turn off the monitor and close the MBPro, then turn it all back on, the TB windows are back on the MBPro. This isn’t happening with my other apps (Curio, PDF Expert, etc.), only with TB. So I keep dragging them back over to the external or using the Window menu to send them over. This is, I suppose, a fairly minor thing, but it is driving me nuts for some reason (not a long drive). Has anyone else experienced this? Any ideas how to fix it?

Thanks in advance,
Bob

I certainly don’t see this on Mojave retina MBAir-2019. I commute between various workplaces and work on laptop only or different brand/size screens in different places (LG 23" 4k at home, normal iiyama 21" in the Uni lab). tBX document windowss generally open where I last saw them in that place. I say ‘generally’ as I use a lot of docs and change views/# of windows quite frequently.

So, Catalina issue perhaps?

Just a quick visit with Google on “Catalina external monitor issues” provides a lot of threads on various issues on this topic. I’d start there.