- open the attached document
- press the Cursor at the start of the second item in the bullet list
- press "Tab"
=> The whole bullet list moves to the right. As you can see in the status bar, the
   items have not been demoted, but instead the indents of the numbering have
silently
   been increased

Doing the same on the third item in the list (which is the second item on level
1), the problem does not happen.

fs->od: As discussed. This bug probably results from the "feature" that pressing
Tab on the first-ever item of a list should change indents. It seems that
additionally, this is done on the first level-1-item on the list.