For example, the
Selection option allows you to export animated GIFs like the followings:
The first one shows the vertices and the hull of selected meshes, the last one shows the outline of selected region attachments.
Regarding the UI bug of the export window, I have confirmed it can be reproduced and we will fix it. As always, thank you for reporting!
I have created an issue for the UI bug:
It seems to not be a bug related to the
Selection option because it also occurs in v4.0, but in any case your report helped us find it.