repository change in Librewolf

[smartshogu]

Reporting a bug 🐛

Librewolf changed the structure of their Debian repository: https://librewolf.net/debian-migration/

Expected behavior

deb-get update will run smoothly

Actual behavior

while librewolf is installed following error message pops up

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://deb.librewolf.net bookworm InRelease: The following signatures were invalid: EXPKEYSIG D29FBD5F93C0CFC3 Malte Jürgens <maltejur@dismail.de>
W: Failed to fetch https://deb.librewolf.net/dists/bookworm/InRelease  The following signatures were invalid: EXPKEYSIG D29FBD5F93C0CFC3 Malte Jürgens <maltejur@dismail.de>
W: Some index files failed to download. They have been ignored, or old ones used instead.

Steps to reproduce

apt-update

System information

/etc/os-release

PRETTY_NAME="Debian GNU/Linux 12 (bookworm)"