Comment 20 for bug 1585332

IMO detecting dark/light theme from the desktop would solve the most annoying usability problem and can be solved by snapping two theme variants.

Matching the exact widget set versions of the system may not be important and even be less appealing than bundling for example newer GTK themes assuming snaps are heavily used for backporting and newer bundled themes look more modern/look simply better. Showing the newer theme could be seen as demoing the new look.

Just my 2 cents.