@Walter Hinteler,
Even if the movement's openly far-right founder has left, the supporters are there to stay: sympathizers who routinely insult politicians as traitors and vilify journalists as the lying press; people who appear to be bitterly disappointed by Germany and it's free market economy 25 years after the peaceful fall of the Berlin Wall and reunification.
I do think that they can't be ignored but that society must try to convince mere followers to separate from the true far-right extremists.
The easiest is, in my opinion, to show them at first that all what they've done is by virtue of democracy and our constitution - the latter is their's as well.
But I suspect, nothing will be enough to convince all of the PEGIDA movement's followers, especially those critical of Islam and religion, to give Germany in its present form a second chance.
At least, we have shown and proved that we aren't as silent as our ancestors during the Weimar Republic times, the wast majority of Germans doesn't want a new 1933-period.