Can't edit Collection Answered
I made a collection (https://www.instructables.com/id/useful-stuff/ ) that can not be edited or unpublished. I addition, the graphical feedback after trying to add something was quite misleading by showing a green checkmark along with the error statement (see image below)
Sorry for crossposting the topic to the FAQ section (in https://www.instructables.com/community/How-to-edit-my-Collections/ ) - I now realize that it must be a bug. I also tried to reproduce the error by making a new collection with the same content. However, this new collection can edited and unpublished without any problems.