Chaging default browser for GNOME on Debian

Problem position

I have chromium and firefox-esr installed. I want gvfs-open to default to the latter when opening a web URL.

Alternatives

There are /etc/alternatives entries for x-www-browser and gnome-www-browser that can be manually edited using

# update-alternatives --config gnome-www-browser
# update-alternatives --config x-www-browser

Unsuprisingly, this won’t have the desired effect. Life would be too simple…

GNOME MIME

The default browser for GNOME applications is determined using gvfs-mime. Per-user overrides can be specified in ~/.local/share/applications/mimeapps.list. System-wide defaults are generated by update-desktop-database and stored in /usr/share/applications/mimeinfo.cache.

Quoting https://wiki.debian.org/MIME:

The mimeinfo.cache is basically a raw reverse cache for the .desktop information. There is no way to define priorities in it. To be able to specify default applications, a mimeapps.list file (previously named defaults.list up to debian 5) must be created. It can be system-wide (in /usr/share/applications or a subdirectory) or user-specific (in $HOME/.local/share/applications).

And indeed the fix was to reorder the list from mimeinfo.cache, and create the following file:

plain /usr/share/applications/mimeapps.list [Default Applications] x-scheme-handler/http=firefox-esr.desktop;chromium.desktop;google-chrome.desktop; x-scheme-handler/https=firefox-esr.desktop;chromium.desktop;google-chrome.desktop;