Sudden change - program is causing Steam and video games to go from maximized to windowed without permission

Lately, Webroot (WR) has changed.  It’s taking longer for my computer to release control of the network to me (i.e., I can’t log onto Steam until WR finishes whatever it’s doing).  This delay has become longer and longer, and is also starting to slow down or interrupt my other programs, especially when it decides to update after midnight local time.  At that point, it basically locks up my entire computer until it’s done.

WR never used to do this, it used to update slowly in the background and not interfere with my work and gaming.  I bought WR after going through all the others because WR did NOT disrupt my programs.  It is now starting to disrupt my programs a lot, and my computer isn’t slow (I’m running an Intel I7-5930K CPU).  However, the latest problem is that when I log onto the Steam gaming service, I will be fine until I go to play Fallout 4.  I'll load it up, then within a couple of minutes of actually getting into the game, something is windowing both Steam and Fallout 4 (with a complete change in resolution).  This is unacceptable, no program should be interrupting my games like this without permission from me.  Everything should be running minimized with no focus switching, nor forced windowing.  The slowdowns have only been in the past couple of months, and the windowing just started this week.  I put up with the slowdowns, but this is the last straw.  In any other game, the game will probably crash (and I still have crashes with Fallout 4, so I consider myself lucky so far).  I need a solution to fix both of these problems.  I need to track down whatever program, including WR, is causing these disruptions, and to fix them.