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Yes, I did receive your PM messages, but just saw you second now.
(there used to be an indicator for PM's received in the header of this site)
And indeed, your first message and some internet research set me to the same solution, although mine is extended to be for all links (you don't need to specify all used id's for the anchor links) and takes also the screen width in account, as there is no floating header for the small screens.
Many thanks for your help!