Akregator: Duplicate article entries with some feeds

Hello.

With some feeds like Debian Micronews, Chaos Computer Club and several users I 
get each article twice in the article list¹ ². When I delete the duplicate at 
some point it shows up again, probably by being downloaded again.

With other feeds like Dot KDE org, Heise Open and others I don´t see this 
duplicate article issue.

I didn´t find a bug report, forum entry or anything else in a quick research… 
and I don´t find anything obvious in this mailing list either…

so am I alone with that issue?

I am still with Akregator 16.04. Still waiting for 17.08 packages to be 
handled by FTP masters (due to change in packaging layout some packages are 
new and require manual handling by FTP masters).

[1] https://micronews.debian.org/feeds/atom.xml
[2] https://www.ccc.de/de/rss/updates.xml

Thanks
-- 
Martin