After having added a new content type in a new group from the main SharePoint site, I went into one of my sub sites and then to a document library. I wanted to add the new content type to the new menu in that library. I went into library settings > Advanced settings > Allow management of content types? and set this to yes just for this document library. The description to the left of this question states "Specify whether to allow the management of content types on this document library. " In advanced settings I also set Opening Documents in the Browser to client and I left the list experience option as Default experience for the site.
I have now found whatever document library I go into on the entire site and then subsites the new > edit new menu option now shows for every document library in the SharePoint environment. If I change Allow management of content types back to No, the new menu option is removed completely from the document library but the new and edit menu option remain on all other document libraries in the SharePoint site. I am an owner of this site and subsites. I am concerned other standard users will start to change the new menu themselves.
Please advise how I can turn off the new > edit new menu option off and on for all document libraries in my site and subsites. Thank you for your help on this matter.