When enabling live Wikipedia data on reading web staging I noticed that the edit link was behaving strangely in Vector. After some investigation there is a bug. Fixing it will make this problem go away :)
In MinervaNeue the method doEditSectionLink is supposed to create an edit link for all headings
In MobileFrontend the MobileFormatter removes any elements which match .mw-editsection. Confusingly it also adds a toggling indicator to headings to avoid a flash of unstyled content. The former is a noop, as edit section links are handled by Skin::doEditSectionLink. The latter is badly documented.
The MobileFrontend mw-editsection code should be removed and the toggling indicator documented better.