Steps to reproduce:

• Resize browser to 864px
• Focus the search input (click on it)

Observed result:
The close icon is misplaced:

Expected:
The close icon at the left side of the search input should look like:

It seems, that the style for the search input and close icon changes for a "tablet" size (LESS variable @wgMFDeviceWidthTablet), while they should change for a "desktop" size, only (LESS variable "wgMFDeviceWidthDesktop").