Show browser window and Word or Mail at the same time?
Since I've switched to Mojave 10.14.3 I am unable to keep my browser window and my email or Word window open on the same desktop. The screen swooshes between them. I can view Mail and Word together. I can view my calendar and Word together. But, I cannot view anything with my browser except my another browser window. I used to be able to keep everything open on the desktop and just toggle between them. How to fix?
Hmm, it certainly sounds like full screen mode, but... that mode wouldn't allow overlapping browser windows either, so it does sound like a setting somewhere has gotten corrupted.
If you've recently done the upgrade/update it might be worth doing a Safe Mode restart (or Onyx cleanup) to clear out caches and "cruft". (I'm assuming you've already tried a normal reboot?)
Otherwise try flipping the browser into and out of full screen mode.
Also, are you running any 3rd party software for managing window arrangements - like Moom?
Sounds like you might have your browser set to open in its own desktop. Opt-click on the browser icon in the task bar and see what it says under options.
Assign to: This desktop, all desktops, none. If it isn't already, change it to none.