This is maybe a different description which could be considered a different bug but: (both with Firefox 38 under Linux Mageia 4 and with Firefox 40 under Windows 10)

• when I click on the "See also" link in the description above to display it in a new tab, and just as Mandruss describes inside that link, I am taken to a place in the page several screens lower than the "Section link malfunction" section,
• the same thing happens when I reload the page with Ctrl-R, the only difference is that it can be seen better that the page is first taken to the right place for half a second and then to a different place (when opening a new tab this can be seen only sometimes),
• if from that place I use Ctrl-L to focus on the address bar and I press Enter, I am taken to the right place.

I've also been seeing the same issue as Oliv0 for a while.

@Jdlrobson: which tags or project does the reading team use to stay abreast of such issues?

Sounds like whatever does the collapsing needs to refresh the hash. e.g.

tmp = window.location.hash;
window.location.hash = '#';
window.location.hash = tmp;

We do this on MobileFrontend after collapsing sections. What code does that collapsing for Vector - mw.collapsible - or is this done via a site script?

I'd suggest adding skin projects to the card e.g. Vector and Monobook (side note we really should have more projects for mediawiki core given it is so big - a #MediaWiki-skins or #MediaWiki-js would be great here)

In T110770#1615318, @Jdlrobson wrote:

We do this on MobileFrontend after collapsing sections. What code does that collapsing for Vector - mw.collapsible - or is this done via a site script?

As best as I can tell, it is a RL module called jquery.makeCollapsible. There is also some nasty old NavFrame trickery in enwiki's Common.js which might need to be looked at.