I have a custom element in our dita application called "festofig" which is a specialization of "section".
I want this element in the Show Filter of the Link/Xref Tab.
Idea: Make the Show Filter customily extensible.
Only a few fix(?) elements are available in the Show Filter (table, fig, fn, section) yet.
I am not sure if this feature/situation was even considered yet.
The business impact is the user has to use "All elements" instead, which is in most cases a very long list.
This slows down finding correct elements and makes it very uncomfortable.