Previously, it was possible to click between two image diff modes and

invoke the image mode changed function (due to padding). Now, the class

is directly on the <a> tag instead of the surrounding <li> tag,

which prevents this issue. This was causing an error (due to a missing

data-mode attribute on the <li> (the event target) that caused the

image review UI to stop functioning.

Clicked between two image modes. The image review UI no longer breaks.