Steps to replicate the issue:

• on mobile from Special:Homepage go to any SE articles (not Structured tasks), e.g. https://en.m.wikipedia.org/w/index.php?title=Jumblies_Theatre&gesuggestededit=1
• The page - =Jumblies_Theatre - will display the Help button

What happens?:

• while on the page click on the Echo notification button - the overlay e.g. https://en.m.wikipedia.org/w/index.phptitle=Jumblies_Theatre&gesuggestededit=1#/notifications will still display the Hellp icon

• click on Search - the Help button is also will be displayed

What should have happened instead?:

• if you click on Notification icons or the Search field not from an article with SE, the Help button wouldn't be displayed.
• Having the Help button on pages where it's not supposed to be, might be confusing for users.

Software version: wmf.6

Other information:

• the issue (the Help button is "stuck" and gets displayed on the overlays, seems to be isolated to the cases described above.