.navbar-collapse is not properly cleared below 768px

[gocemitevski]

CKAN Version if known (or site URL)

2.8 with Bootstrap 3

Please describe the expected behaviour

After the 768px break point, .navbar-collapse should be displayed in full width, without negative margins.

Please describe the actual behaviour

After the 768px break point, .navbar-collapse has negative margins, is not properly cleared of floating elements and does not have a full-width top border.

What steps can be taken to reproduce the issue?

Open any page in CKAN and toggle the main navigation (.navbar-collapse) after the 768px break point.