Feed from AdaCore's blog not working properly

I have been subscribed to AadCore's blog feed for some time. Its feed content was OK for some time, and suddently does not work any more (also for some time already, I just did not have time to tackle the problem). I could not get any new feed, altough I could see new blog entries posted. With both feed readers Liferea and Thunderbird, I could not get it display any feed.

After invesitigation, I found the feed respone content is not conform to the standard, it contains a new line at the start of the feed, and has javascript block at the end of the response.

When doing further investigation with Liferea, I found that it supports a very useful feature, a conversion filter. After try and error, I formuate a sed filter commands that could remove all those invalid entries in the source:

sed  -e '1d'  -e 's/<\/rss>.*$/<\/rss>/' -e '/<\/rss>/q'

The first script removes the first line, the 2nd script remvoes all characters after </rss> in the same line, the 3rd scripte stops when encounter </rss>, effectively remove all contents after the matching line.