Memory issues are getting a lot of attention in v11.30. But class designers are also affected. I was surprised to see the map open and working. When checking, not all class designers are set. It has been reset! It is difficult to restore these settings, such as triggers, so take this into account. How about everyone? I think many people use class designers on 1vs1 maps. check it out!
We're aware and working towards a fix. Thanks for posting!