Fixed Skybox breaks pressing ESC twice after using objectplace

[GLide KS]

I have no words for this.

 

[Monster Iestyn]

Actually, it's because you placed a new item in objectplace mode that made the skybox break. This is a bug we've known about for a while now but (obviously) haven't gotten around to fixing yet.

 

[SteelT]

Made a fix for this myself here.
https://git.magicalgirl.moe/STJr/SRB2/merge_requests/319