Just to add a little.
In years passed I rode pre65 trials motorcycles which had to be "road legal" to compete.
We never fitted lights but had to have a rear reflector fitted.
I regularly road my bike on the road so for safety reasons I fitted a rear brake light.
The next MOT the bike failed because technically as I had a rear light, I had to also have a front light !!!
So to get an MOT I had to tape over the rear brake light. After the MOT pass I removed the tape and continued to ride the bike!!!
By the way are hand signals still legal as there are no longer in the "highway code".