Thunderbird mail and window size

I use Thunderbird as my email client and have been having a lot of problems getting my desired settings to stay put. when checking some of the screens I need to use on my larger computer, I have found that several of the windows have an OK at the very bottom of the page, and that will set my preferences. However, these particular windows are not resizable and the "OK" to save the setting is not appearing on the AAO screen. For some of the windows I was able to access the OK by autohiding the taskbar, but there are a few where the bottom of the window is still not visible. Is there any way around this? I have tried doing a CTRL S to save, but it does nothing.

 

1. Try alt+spacebar > M > up arrow to nudge the window higher on the screen.

This may not work, though. I found with a couple of programs, the bottom of the window, when revealed that way, cuts off before the OK button. In that case...

2. Connect the laptop to a full-size monitor while configuring program settings.