we have now got the answer from the danish Government Authority.
We asked them: Are there any requirements regarding having address/connection to Denmark,when EU-citizens currently living in Denmark go to another EU-country looking for job, and at the same time receiving 3 months of Unemployment benefits ("Dagpenge") from the danish A-kasse.
The answer from them:
It is a requirement that the member must be available in Denmark immediately prior to the date of departure.
This means that the member must be entitled to unemployment benefit on the day that he/she travels from Denmark. You can for instance be entitled to unemployment benefits if you have graduated with a danish education. Otherwise you can be entitled if you have been working 1.924 hours during the last 3 years.
Finally, this means that the member must reside and stay in Denmark on the date stated as the date of departure on the application (PD U2). The PD U2 application/document is needed when you want to export the 3 months of Unemployment benefits/Dagpenge to another EU-country. You apply for this by asking your A-kasse.
After the departure abroad, there is no longer a residence requirement for Denmark, this means that it is not required to maintain residence/address in Denmark. There is no further connection requirement in relation to residence in Denmark.
It is also of no relevance if the member leases or buys housing in the EU / EEA country where the member seeks work.
However, the member must maintain the membership of an Unemployment Fund ("A-kasse") in Denmark, in the period in which he/she applies for Unemployment benefits from Denmark. During this period, the member must possible to be contacted by the danish A-kasse.
Finally you are allowed to unregister from the Danish Population Register ("Folkeregistret") from the date of departure.
So the answer emphasizes that all that matters in relation to keep the right to Benefits/Dagpenge for 3 months is that you have address in Denmark at least up to the day of departure according to the PD U2 document.
Hope this will help you, otherwise please comment on this.