Thanks for the bootstrap link!
I just realised that I need to update the wallet to v1.9.9 too. :-)
Question, what is the next step, once I have downloaded the bootstrap.
-> Where/In which directory I need to copy into the file?
Do I need eventually rename the file bootstrap.dat into "blk0001.dat" and delete the existing one with this filename?
I apologize, as I don't really. Just join the discord channel and they will help you out I'm sure. I can't remember how I got mine synced but I know there is a blockchain download out there someplace.