In User Preferences (for example), the labels next to checkboxes are not actual
<label> elements, so they can't be clicked on to toggle the checkbox. Making
them actual labels would be good for accessibility and usability.

They are (mostly) correct in Add Content Page, and Settings - News module ->
Options, although being above the checkbox makes it less obvious that they are a
clickable label.

Incorrect/missing in Search module options.