Once you’ve done the above, delete everything above this line.
^there really are multiple collapse indicators in this example (a total of three, in fact)
Did you follow the troubleshooting guide? [Y/N]
This is explicitly an issue with the editor, it happens in both editing modes. If you enter Reading View, there will be only a single collapse indicator for this entire structure, and it will be at the start of the first 1. the first image, as part of the top-level list item, will remain visible even when that indicator is toggled; the second image, as part of the sublist, will be visible based on the toggle state
image and comments provided by @sailKite