Setting Default Browser on Linux

I’ve been using Ungoogled Chromium for quite a while now, but some time in the last few days it stopped played YouTube videos successfully. The symptom was that after 19 seconds, the video would stop playing and a spinner would display forever.

This turned out to be a known bug. The suggested fix was to enable the “Disable WebGL” flag in chrome://flags, i.e. disable WebGL features. This does seem to work, but I don’t know yet how this will affect other web sites that I use.

That’s all well and good, but during my experiments, I had started to use Firefox again (which did not have the YouTube problem) and I told it to make itself the default browser. Then after I discovered the fix for Ungoogled Chromium, I tried to tell it to make itself the default browser again in its settings. But that didn’t seem to work.

In an attempt fix the problem, I ran this command:

sudo update-alternatives --config x-www-browser

That displayed four alternatives, one of which was /usr/bin/chromium, so I selected that. I tested it by running this command to load my own web site:

open https://www.bloovis.com/

But it still ran Firefox to open the site.

There is another way to set the browser in Linux, using xdg-settings. I ran this:

% xdg-settings get default-web-browser
firefox.desktop

and that told me that Firefox was still the default browser.

I was able to verify that a similar desktop file existed for Ungoogled Chromium:

% locate chromium.desktop
/usr/share/applications/chromium.desktop
% tail -1 /usr/share/applications/chromium.desktop
+Exec=/usr/bin/chromium --incognito
% ls -laF /usr/bin/chromium 
lrwxrwxrwx 1 root root 53 Jan 25 07:40 /usr/bin/chromium ->
  /usr/bin/ungoogled-chromium_128.0.6613.119-1.AppImage*

So that told me that the following command would set the default browser to Ungoogled Chromium:

xdg-settings set default-web-browser chromium.desktop

And using the open command again showed that it did indeed work.