User modified colours - background colour for focused item defaults to white

[accessiblewebuk]

Tested using Firefox colour settings. When arrowing through the results, for the first five the focused result is indicated in the box but has a white background. Don't know what the user would expect in terms of a background, but as they have changed settings this may not be readable for them. See https://accessibility.blog.gov.uk/2017/03/27/how-users-change-colours-on-websites/ for further information on the sorts of things that need to be considered.

[vanitabarrett]

We recently discussed this as a team and we're unsure if this is default behaviour in Firefox. We should investigate first.