I'm currently using org-mode version 9.1.14, where everything seemingly works fine.
The problem is, when I upgrade to the latest version via the packaging system, one particular headline no longer folds and hides its children, although the visiblity properties are identical to other headlines, and the way its children are structured as well. On startup the custom property gets ignored, it's not folded, and all its children are visible. I've upgraded to the latest emacs version, to see if that makes a difference, but the problem persists. Not sure where or how I should start to track this problem down. Here's the offending headline. * DONE 2017 [462/462] abc,cde, efg, hij, klm :PROPERTIES: :VISIBILITY: folded :END: ** DONE Dezember [34/34] abc, eds :PROPERTIES: :VISIBILITY: folded :END: CLOSED: [2017-12-31 So 00:19] - CLOSING NOTE [2017-12-31 So 00:19]