Single window/application open at a time

Whenever I open an application all other windows minimize. This started while I was working on my computer this morning. Does anyone know what might have caused this? It is like I accidentally typed a command I didn't know I was typing.

Device information:
-MacBook Pro (Retina, 13-inch, Early 2015)
-Two Dell U2412M external monitors
-macOS Catalina 10.15.4
-BetterTouchTool version: 3.374

No need to respond. I figured out the issue.

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