chromium-browser: ERROR: not connected to the gnome-3-28-1804 content interface

Solution 1:

OK I found this solution on the snapcraft.io forum

snap connect chromium:gnome-3-28-1804 gnome-3-28-1804:gnome-3-28-1804 

doesn't output anything but after I ran it, chromium ran again happily.

I'd love to know why it got broken tho!