Legality of tv screens on the side of vehicles

[AlVal]

garbage trucks now sporting big digital advertising screens on their side - I get the feeling if this was a boy racer with a tv screen on the side door panel, they'd be pulled over pretty quick - I had a quick look at legislation but couldn't specifically find anything against this:

https://twitter.com/davidgarnold/status/8316531119...

is it seriously legal? I think i could argue it would cause white light to be visible from the rear , and red light to be visible from the front, depending on how they define 'from the front' and 'from the rear'

[AlVal]

Oakey said:

I'd love to know what their sales pitch is!

"Good morning Sir, would you like to associate your business and brand with trash?..."

yeah, the marriage proposal on the side of one I saw raises similar questions...