[ticket/12853] Change navbar ACP from skip- to last-responsive

PHPBB3-12853
Merge pull request #2739 from PayBas/ticket/12853

[WIP][ticket/12853] Change navbar ACP from skip- to last-responsive

* PayBas/ticket/12853:
  [ticket/12853] Change navbar ACP from skip- to last-responsive
Merge branch 'develop-ascraeus' into develop

* develop-ascraeus:
  [ticket/12853] Change navbar ACP from skip- to last-responsive