bullseye-backports - libicns
The packaging branch at (https://git.code.sf.net/p/icns/code/ -b master) can not be reached.
This problem may be intermittent, e.g. if the hosting site is temporarily down.
If the repository has moved, please update the Vcs-* headers in the package and upload a new version.
You can also update the Vcs locations on vcswatch.