I recently came across the following case where the mobile view ends up hiding sections and their headers when collapsed (which is default behaviour on my mobile).
Examples:
Desktop: https://commons.wikimedia.org/w/index.php?title=User_talk:Holger.Ellgaard&oldid=130228207
Mobile: https://commons.m.wikimedia.org/w/index.php?title=User_talk:Holger.Ellgaard&oldid=130228207
Using the two examples below we see that the desktop view shows 30 headings whilst the mobile view only shows 12 headers (when collapsed). Expanding the last of these reveals a new collapsed header which when expanded reveals a new header and so on (for a few headers). The last of these reveals the remaining 14 headers.
So there are 3 headers which misbehave and makes the mobile frontend believe that any later sections should be treated as subsections (i.e. collapsed and hidden by default).
Whilst the source of the weird behaviour is probably that the header includes a template it is still a valid bug as
- one would expect the mobile and desktop interface to resolve the problem in the same way.
- section links to any "hidden" sections fail to work since the previous header collapses it e.g. compare https://commons.m.wikimedia.org/w/index.php?title=User_talk:Holger.Ellgaard&oldid=130228207#File:Briefmarke_LT_Fluegge.jpg and https://commons.m.wikimedia.org/w/index.php?title=User_talk:Holger.Ellgaard&oldid=130228207#File:Stadsplan_Pl_7800_Gamla_stan.jpg
This affects alpha, beta and stable
Version: unspecified
Severity: normal