My work-provided Windows computer died last week, and so I have been using my Dell Inspiron 1525 with LXDE/Lubuntu 18.04 with the lightweight Falkon web browser which I launch from the Application Launch Bar at the bottom of the screen. However sometimes the chromium web browser was being opened, for example when I click a link in emacs. Here is how I set Falkon to be used instead.

I found a related article on stackoverflow with a response from Lawful Lazy that helped me find a solution that uses xdg-settings.

First I created the file ~/.local/share/applications/falkon.desktop with the following contents:

[Desktop Entry]
Comment=Falkon minimal web browser

Then I ran the command line

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

Test it works via