Back in the good old days, before aerodynamic wraparound clustered headlights with 3D LED arrays, you were handed a pack of stickers for your headlights before traveling to or from the UK.
When applied correctly, these stickers blocked the part of the beam that would blind oncoming traffic, when driving in the opposite side of the road compared to what the headlights were designed for.
On the picture below from boxing day 1993, you can see a sticker mounted on Laura. Laura is a LHD model, so on her return to her birthplace in Solihull, she had to be partially blindfolded.
In some headlights, you can actually se the part of glass that gets covered. Below you can see a triangle on the right side.
Can you remember traveling with these stickers, then please leave a comment below.