When you click on the Custom Custom quickly (doesn't need to be as fast as I do in the video), your UI won't show up.
I assume this bug get's triggered when you click on a button before the UI pans in completly.
And I dunno if you have to click on skirmish before or not, but I did.
*Steps to Replicate:*
- click on Singleplayer
- Click on Skirmish
- back out of Skirmish
- click on Campaign
- click quickly on Custom Campaign before the UI finished paning into the screen
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