Mumble incompatibility between Bionic and Focal

[René Walendy]

Hi all,

we're currently having some issues with mumble-server and the mumble
client between the Bionic and Focal LTSes. The maintainers of
mumble-voip on Github pointed me to your mailing list as they're
apparently not the ones maintaining their software's Ubuntu packages.
Maybe you can help me with this:

The Bionic client and server (which are stuck at 1.2.19) can only use
TLS 1.0 since it is built against Qt4's old SSL library. The Focal
repository ships 1.3.0. That client will refuse to connect to servers
with old crypto, i.e. Bionic servers, and the Focal server won't accept
Bionic clients. That creates an incompatibility between two supported
LTSes, which led to quite some frustration among my users recently.

The only workaround I know of so far is to disable the TLS restrictions
for Mumble on Focal, which is exactly what Focal doesn't want after the
efforts to bump the required TLS versions up. Since Bionic will live for
another three years, I think that continuing to provide software using a
twenty year old, deprecated crypto protocol should be avoided wherever
possible.

To resolve this issue, is it possible to bring the 1.3.0 mumble and
mumble-server packages to Bionic?

Best regards,
René