Viewport displaces when toggling table of contents

[postinternetsyndrome]

When opening or closing the table of contents panel, the entire viewport shifts several pages; up when opening, down when closing. This is especially disorienting on mobile devices.

[rubenpieters]

Thanks for the report! I have reworked some part of the TOC in our internal version, so I expect this to be improved in the next CR update when we update the online version.