Bugfix SUP-882
The position of the floating toolbar was not correct,
if the page was vertically scrolled and there was insufficient
space above the activated editable. The toolbar was not positioned
right under the editable, but with some distance.
This has been fixed now.
Bugfix SUP-1060
When calling .pad() for a block twice, it could happen, that
two adjacent landing spans were added. This will be avoided now.