Does this only happen with this one specific layout? In this one specific file?
If you have back up copies, test them to see if you get the same behavior.
If it's only this one layout, you may need to remove this layout from your solution and create a new copy of it. When making such a copy, do not copy any objects from the copy that crashes as you may copy the problem along with it to the new layout.
And since 14 is newly released, we are still documenting bugs that it may have introduced. If you think that this is a bug, please post a report over in Report an Issue.