Steps to reproduce:
1. Edit an event with a running workflow
2. Warning says:
"The current event can currently not be edited as it is involved of an active transaction."
3. Click on X.
4. Click on another one of the tabs in the modal dialog.
The warning comes back.
Also, the warning text is ungrammatical and needs improvement.
Warning should go away when you click X and not come back until you dismiss the modal dialog.
For a less intrusive reminder, it might be helpful to add a "locked" icon, possibly to the left or right of the "Event details" text at the top.
Suggest rephrasing to:
"This event can not be edited as it is being updated by an active workflow."