The new HeaderView, which provides a responsive menu at the top of the

page, had some performance problems and negatively affected the

dashboard.
While resizes were throttled, the callback ended up doing far too much

work when in non-mobile mode. It changed CSS on elements, changed

visibility, and set up animations, every time there was a resize. This

caused a lot of churn on the page, slowing resizes. This logic only

needed to happen when the mobile menu changed state, so we now prevent

it from happening unless we know we're changing that state. Resizes are

a lot faster after this.
It also no longer wraps $(window) all the time, but instead keeps a

handle to a pre-wrapped $(window). That offers another speedup in the

resize handling.
One of the styles applied in the resize handler was an 'overflow' on the

body element. If a page (such as the dashboard) had its own 'overflow'

property set, it would be overridden, breaking page layout. Instead of

hard-coding the default value when the mobile menu closes, we instead

remove our custom property, allowing the page to fall back on the CSS

rules.
The last little fix is that the logo was set to navigate to the root of

the domain, instead of the site root, fixing the link on subdirectory

installs.

Tested resizing. Much smoother.
No longer hit issues with scrollbars appearing on the dashboard page. Verified

that the overflow property was no longer set unnecessarily.
Tested that the logo link worked.