Comment 1 for bug 1725032

Hi knz,
in an Artful system as of today I can't reproduce your issue.
It is working fine.

# ldd /usr/bin/tmux
        linux-vdso.so.1 => (0x00007ffe41ff0000)
        libutil.so.1 => /lib/x86_64-linux-gnu/libutil.so.1 (0x00007f95420f4000)
        libutempter.so.0 => /usr/lib/x86_64-linux-gnu/libutempter.so.0 (0x00007f9541ef1000)
        libtinfo.so.5 => /lib/x86_64-linux-gnu/libtinfo.so.5 (0x00007f9541cc8000)
        libevent-2.1.so.6 => /usr/lib/x86_64-linux-gnu/libevent-2.1.so.6 (0x00007f9541a76000)
        libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007f954185c000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f954147c000)
        libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f954125d000)
        /lib64/ld-linux-x86-64.so.2 (0x00007f9542584000)

The version of the tmux package is at 2.5-3build1.

It's depends are on:
$ apt cache show tmux | grep Depends:
Depends: libc6 (>= 2.14), libevent-2.1-6 (>= 2.1.8-stable), libtinfo5 (>= 6), libutempter0 (>= 1.1.5)

And libevent is on
dpkg -l libevent-2.1-6
=> 2.1.8-stable-4

Could you please recheck after a full update/upgrade and then:
1. compare the package versions I referenced on your system and report them here
2. report the ldd of tmux in your case
3. check where your tmux comes from via $ apt-cache policy tmux