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Libera have made a webchat client available. This change builds on #12127.
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jonathon Fernyhough <jonathon@m2x.dev>
Closes #12251