Debians apt now warns the user in several possibly insecure situations.
For the jitsi repository the warning is:
`W: http://download.jitsi.org/deb/unstable/Release.gpg: Signature by key
040F57608F84BAF1BF844A62C697D823EB0AB654 uses weak digest algorithm (SHA1)`
The solution would be to improve the algorithm to SHA256 or SHA512 as
stated on this wiki page:
I think this should be added as an issue to the tracker.