Could it be that you have installed chromium both from ubuntu packages
and from the snap, by any chance?
Can you share the output of the following command, run in a terminal?
xdg-settings get default-web-browser
** Changed in: chromium-browser (Ubuntu)
Status: New => Incomplete
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to chromium-browser in Ubuntu.
Chromium complains that it's not the default browser when it is the
default according to Gnome Settings
Status in chromium-browser package in Ubuntu:
(As seen in a daily build of Ubuntu Budgie 18.04 32bit downloaded
See attached screenshot.
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