XF 1.5 Chrome using Background-size cover

[expanserpb]

Trying to ensure that backgrounds are covering properly.

I'm using XF 1.5 and UI:X with ADstyler.

I can set the size to cover in two places:

Appearance> Styles > Stylename > Style Property Groups > [UI.X] AD Styler
And set Body Background Size to "cover"

Appearance> Styles > Stylename > Style Property Groups >General > HTML

Include in misc:
-moz-background-size: auto, cover;
background-size: cover;
background-attachment: fixed;


However, whilst IE is behaving (eugh had to open IE) in chrome I still get this: https://i.gyazo.com/382424f4ce2cbc4265dc498d08f8ad23.gif

Any thoughts on where to look next would be much appreciated.