Replace url() with path() for dashboard url

It's not better to use the relative dashboard url generated with the
path() twig function instead of the absolute url using the url()
function?

I noticed in a project of mine (the hosting server have some special
settings regarding the public hostname) that the dashboard url is wrong
generated using url(), with path() it is perfect.
Merge pull request #2519 from samuel4x4/master

Replace url() with path() for dashboard url
Replace :before with :after

The sort arrow being right, it makes more sense to use pseudo-element after
Merge pull request #2535 from roukmoute/patch-2

Replace :before with :after
Merge remote-tracking branch 'origin/master'