It also generates an iterator error when toggling multiple tasks on or off at a time.
In the image attached you will see 2 tasks that are toggled as "on", but I changed the toggle to off before refreshing the project UI for this project.
Status changed from In progress to Refused
Please split the project to sub-projects using "Stop & Start" task.
One project should not include more than 10 Build tasks because of performance issue.