Ctrl+z while playing in the blueprint editor will undo history

When pressing play within the blueprint editor, if you use control & z, it'll revert your changes you've made to the blueprint. Which could cause people to lose their progress in their blueprint template.

1. Create a blank template
2. Open the level blueprint
3. Create 'Left Ctrl' node
4. Create 'Z' node
5. Create a 'Print String' node
6. Connect the nodes together
7. Press play in the blueprint editor
8. Do not focus to the viewport, just start pressing control + z
9. The nodes and pins will delete when they shouldn't, and they will not be returned after pressing stop.