I have solution for you. If your system crash, open the tty (alt + ctrl + F1), log in. Kill the Gnome process and then type
Code:
gnome-shell -d :0 --replace
This command will open the gnome-shell on the standard X display. There “—replace” option is used to replace existing window manager. But now the system does not look normal and it won’t work properly. Themes no longer work at all. But the advantage is you can still able to safely close all apps without losing your data. Then you can safely reboot.
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