Link to Libera, Matrix instead of Freenode

The project has moved away from Freenode as an IRC network[1], and there
is now a quite large channel on Libera.  As such, we should point users
towards that instead.

This also changes all examples to refer to libera instead of freenode
as, with the recent deletion of all freenode channels, it is perhaps
where most communities are to be found nowadays.

Finally, also link to the official Matrix room[2] as an alternative to
IRC.

Related: https://github.com/NixOS/nixpkgs/pull/129384

[1]: https://discourse.nixos.org/t/join-us-on-matrix-at-nix-nixos-org-migrating-from-freenode
[2]: https://github.com/NixOS/rfcs/pull/94

1 files changed, 6 insertions, 5 deletions

diff --git a/nixos/doc/manual/preface.xml b/nixos/doc/manual/preface.xml
index ded6bdc87de..c0d530c3d1b 100644
--- a/nixos/doc/manual/preface.xml
+++ b/nixos/doc/manual/preface.xml
@@ -18,12 +18,13 @@
  <para>
   If you encounter problems, please report them on the
   <literal
-   xlink:href="https://discourse.nixos.org">Discourse</literal> or
-  on the <link
+   xlink:href="https://discourse.nixos.org">Discourse</literal>,
+  the <link
+   xlink:href="https://matrix.to/#nix:nixos.org">Matrix room</link>,
+  or on the <link
    xlink:href="irc://irc.libera.chat/#nixos">
-  <literal>#nixos</literal> channel on Libera.Chat</link>, or
-  consider
-  <link
+  <literal>#nixos</literal> channel on Libera.Chat</link>.
+  Alternatively, consider <link
    xlink:href="#chap-contributing">
    contributing to this manual</link>. Bugs should be
   reported in