Heading with content tooltip is not visible

[Coffei]

If I have a heading only with the content Tooltip it is not visible in the resulting HTML docs. Root cause is that the heading is assigned an ID of tooltip and there is some style for this ID with visibility: hidden and other properties that make it invisible.

You can check this reproducer: https://github.com/Coffei/ex_doc_tooltip_test

In Github you can see the header Tooltip but if you generate the documentation it is not there.

I think it should not behave this way, the style should be applied on a class which is something the user cannot easily change from the markdown and thus should cause no collisions.

[Coffei]

Amazing response time, thanks!