I suppose that this might require a lot of work but I would highly appreciate if the bookmarks can be rearranged via drag&drop as this would spare the user the effort to hit Edit and manually set bookmark position.
When you are in edit mode, the second button under the bookmark tiles

can be dragged around to move the bookmark, and the arrow buttons on left and right to it will move the bookmark one space left or right respectively. Hope that was what you needed.
Thank you @Q-out for answering again.
@smaragdus, As described above, each Group and Bookmark has controls to move and sort.
@Q-out
Thank you again for the useful tip.
@zombieFox
What was described above really works but I find drag&drop handier because it does not require use of buttons. If this cannot be implemented feel free to close this issue.
@smaragdus Sorry I don't understand. nightTab does have drag an drop on each Group and Bookmark. Is this not working for you?
@zombieFox
Excuse me, somehow I overlooked that the drag&drop button should be active. I am closing this issue. Thanks.
Most helpful comment
@zombieFox
Excuse me, somehow I overlooked that the drag&drop button should be active. I am closing this issue. Thanks.