Hi.
First of all, thank you for Polymode. I've used it with great success for some time now.
Recently I upgraded to Emacs 28.1. Now, when I work in org mode with poly-org enabled, all collapsed source code blocks expand, and the cursor can jump to at different place.
In the two screenshots below I have an org file with five headings each with one emacs-lisp source code block which is collapsed. When the cursor moves into the block in heading 5, alle blocks are expanded and the cursor is moved to heading 2.

