I am very grateful for these efforts. Thank you.
With SelectToSurf, I get the same behavior (select a URL in notepad, hit ctrl-space, the new URL loads into FF, but FF stays minimized).
In FF I have both "Web Browser Links" and "External Links" set to open in the current tab. But setting either or both to "New Tab" does not help. The URLs do open in new tabs, but FF still stays minimized.
I tried setting the "Custom Browser" to FF. The first time only, with Firefox already running, I tried to launch a URL from farr and got a dialog that said: "Close Firefox: Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system." But after closing and re-opening FF, it now works the same with or without the "Custom Browser" (it loads, but stays minimized).
Rebooted. That's been a while. No change.
Reinstalled FF. Again, no change. Admittedly, did not uninstall first. Tried disabling FF add-on "TabBrowser Preferences" (including exit/restart FF), still no change.
Maybe something with one of the other app launchers I was looking at? Killed everything off but farr and still no change.
Can try it on another machine I have at home....