Arrow head on a line

Hello everyone !
I would like, if possible, to have an arrow (to explain to the people that a road is one way only).

A bit like here (the red arrow) : https://prnt.sc/2VBoNmofs0v7

I saw that : https://github.com/slutske22/leaflet-arrowheads but it doesn’t seem to be working here.

any idea how I can get this result?

Thanks a lot for your help !

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