WebM support, but no correct file naming Rated 5 out of 5 stars

When I choose to download the WebM variant of a video on youtube, the naming is not well done. Check this screenshot, it says all: http://img21.myimg.de/DownloadhelperWebMNamingad940.png

This review is for a previous version of the add-on (4.9.7).  This user has other reviews of this add-on.