We got this on our Mp servers for quite some time too, but for me the zoom from toolbar was fixing it always. Problem mostly happens when someone with other monitor resolution/ratio fully zoomed out in editor and saves the mission. i fixed our missions by loading the mission, zoom in a little bit an resave. problem gone for everyone. I don't know why but for me it looks like a problem with the resolution and saving from editor...
for example:
1. i am running on 2560x1080 21:9 , mission saved fully zoomed out -> guys with 16:9 = stuck f10 map ( i dont know about their resolution)
but it was working for me
2. on a event day a user made a mission with 16:9 higher resolution then mine (don't know the exact resolution but higher then mine)
saved fully zoomed out -> i got stucked f10 map
and so on.
saving this missions with zooming bit inwards and resave -> problem gone
sry about english hope you know what i mean