Yeah I didn't think thinset would work here.
There is no room between the nut and the wall for a escutcheon plate.
It is a brand new fitting and a 1/4 turn ball valve so it should be a loooong time before it need replacement. *knock on tile*
I like the silicone idea - given I already have plenty of that. Definitely an area that won't be touched much.
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Patric
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