not always reproducible.
syslog:
Dec 10 01:59:13 unibook gnome-session[1776]: Error sending IPC message: Datenübergabe unterbrochen (broken pipe)
Dec 10 01:59:21 unibook gnome-session[1776]: (epiphany:9245): GLib-GObject-WARNING **: invalid (NULL) pointer instance
Dec 10 01:59:21 unibook gnome-session[1776]: (epiphany:9245): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed
Dec 10 02:01:48 unibook kernel: [57132.245566] WebKitWebProces[5601]: segfault at 10 ip 00007f7b3040493b sp 00007fffad1effe0 error 4 in libwebkit2gtk-4.0.so.37.13.11[7f7b2ef5a000+22a8000]
Dec 10 02:02:03 unibook gnome-session[1776]: Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x4c0000b (Klang)
Dec 10 02:02:58 unibook kernel: [57202.251356] epiphany[9245]: segfault at 6b40 ip 00007f70a3f24bc4 sp 00007ffedd56d0d0 error 4 in libgtk-3.so.0.1800.9[7f70a3e7e000+71a000]
Dec 10 02:03:11 unibook gnome-session[1776]: (epiphany:5858): GLib-GObject-WARNING **: invalid (NULL) pointer instance
Dec 10 02:03:11 unibook gnome-session[1776]: (epiphany:5858): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed
Dec 10 02:03:12 unibook gnome-session[1776]: (epiphany:5858): GLib-GObject-WARNING **: invalid (NULL) pointer instance
Dec 10 02:03:12 unibook gnome-session[1776]: (epiphany:5858): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed
[...]
Dec 10 02:09:48 unibook kernel: [57612.736381] epiphany[5858]: segfault at 34020040 ip 00007f03fe1cebc4 sp 00007fff114c2d80 error 4 in libgtk-3.so.0.1800.9[7f03fe128000+71a000]
Dec 10 02:09:55 unibook gnome-session[1776]: (epiphany:6529): GLib-GObject-WARNING **: invalid (NULL) pointer instance
Dec 10 02:09:55 unibook gnome-session[1776]: (epiphany:6529): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed
Dec 10 02:09:55 unibook gnome-session[1776]: (epiphany:6529): GLib-GObject-WARNING **: invalid (NULL) pointer instance
Dec 10 02:09:55 unibook gnome-session[1776]: (epiphany:6529): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed
Dec 10 02:09:56 unibook gnome-session[1776]: (gnome-settings-daemon:1897): GLib-CRITICAL **: Source ID 29626 was not found when attempting to remove it
Dec 10 02:11:07 unibook gnome-session[1776]: (epiphany:6529): GLib-GObject-WARNING **: invalid (NULL) pointer instance
Dec 10 02:11:07 unibook gnome-session[1776]: (epiphany:6529): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed
---
elementary OS 0.4 Loki (Ubuntu 16.04 LTS based) on a MacBook Pro (Retina)
We are sorry that we do not always have the capacity to review all reported bugs in a timely manner. You reported this bug some time ago and there have been many changes in Ubuntu since that time.
Ubuntu 16.04 (xenial) reached end-of- standard- support on April 29, 2021.
I'm setting the status of this bug to 'Incomplete' as it's not seen any activity for some time. If this is still an issue when using a currently maintained release of Ubuntu then please let us know which one(s) otherwise this bug report can be left to expire in approximately 60 days time.
Thank you for helping make Ubuntu better.