Switzerland.
Shrub/young tree.
Help please.

Is it Frangula alnus.....common name Alder buckthorn?

You are right: Alder buckhorn (frangula alnus.)
Commercial use: manufacture of gunpowder
BTW It is considered an invasive species in then United States.

Many thanks...patsy22april appreciated.
By adding pics here I was able to use id app ...could then double check my facts.
In UK it is not a problem...is rather rare.
Along the way I found several pics named Frangula alnus that were clearly Cornus...one on a UK charity..." The Woodlands Trust"..Ooops.

www is full of mis labelled plants...so annoying.