assertion failure in session2_transport_event

[system] requirement "session2_is_empty(s)" failed in session2_transport_event@../daemon/session2.c:1651

Full stack trace:

#0  0x00007fd603e03624 n/a (libc.so.6 + 0x97624)
#1  0x00007fd603da9ba0 raise (libc.so.6 + 0x3dba0)
#2  0x00007fd603d91582 abort (libc.so.6 + 0x25582)
#3  0x00007fd6044cd344 kr_fail (libkres.so.9 + 0x3e344)
#4  0x0000556d0d49a8cf session2_transport_event (/usr/bin/kresd + 0x338cf)
#5  0x0000556d0d4913d1 session2_event_unwrap (/usr/bin/kresd + 0x2a3d1)
#6  0x00007fd60436ce94 n/a (libuv.so.1 + 0x24e94)
#7  0x00007fd60436d1bb n/a (libuv.so.1 + 0x251bb)
#8  0x00007fd604371d83 n/a (libuv.so.1 + 0x29d83)
#9  0x00007fd604358362 uv_run (libuv.so.1 + 0x10362)
#10 0x0000556d0d48ddc5 run_worker (/usr/bin/kresd + 0x26dc5)
#11 0x00007fd603d93488 n/a (libc.so.6 + 0x27488)
#12 0x00007fd603d9354c __libc_start_main (libc.so.6 + 0x2754c)
#13 0x0000556d0d4801a5 _start (/usr/bin/kresd + 0x191a5)

More context from coredump:

#4  0x0000556d0d49a8cf in session2_transport_event (s=0x556d27667c20, event=PROTOLAYER_EVENT_FORCE_CLOSE, baton=0x0) at ../daemon/session2.c:1651
        is_close_event = true
        is_close_event = <optimized out>
        __func__ = <optimized out>
#5  session2_event_wrap (s=s@entry=0x556d27667c20, event=event@entry=PROTOLAYER_EVENT_FORCE_CLOSE, baton=<optimized out>) at ../daemon/session2.c:1237
        cont = <optimized out>
        grp = <optimized out>
#6  0x0000556d0d4913d1 in session2_event_unwrap (s=0x556d27667c20, start_ix=<optimized out>, event=PROTOLAYER_EVENT_FORCE_CLOSE, baton=<optimized out>) at ../daemon/session2.c:1264
        cont = <optimized out>
        grp = <optimized out>

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