iMac 2017: USB-C Display Inactive After Logging In

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During the installation of Fedora and the first boot process, Fedora 28 properly connected my secondary monitor (USB-C to Display Port cable) as an extended monitor. Immediately after logging in, the monitor shuts off and does not want to display under any of the options with the display settings.

So, we know it works, since it was on during the installation process, but what was it after logging in that would turn the display off? Under the display settings it still shows up, and Fedora thinks that it's there (let's my mouse go into the void of where my monitor should be displaying).

Any help would do!

Specs: (that should matter)

• iMac 21.5" 2017:
• CPU: i7 7700
• GPU: AMD/ATI 560 4GB
• OS: Fedora 28 (Fresh install)