This is a follow-up of MDL-62528, where the behavior of forum permalinks scroll was improved to show them properly placed.

Still, in the testing phase there, it was detected that, using Firefox, the permalink corresponding to the first post in the discussion leads to some overlapping with the nav bar. The issue is not reproducible with other posts neither with other browsers.

Only Firefox and forst posts.

So this is about to:

1) Fix the FF first post case.
2) Replay the testing phase against as many browsers as possible ensuring that both the 1st and the nth posts are overlapping-free.