if I click on a mailto-link in Vivaldi nothing happens. I could locate the problem in xdg-email which is used by Vivaldi to start the E-Mail program.
I checked in the terminal and this is the output of xdg-email:
[michael@michael-thinkpad ~]$ xdg-email mailto:firstname.lastname@example.org /usr/bin/xdg-email: Zeile 619: thunderbird.desktop: Kommando nicht gefunden.
In line 619 I found “THUNDERBIRD” but it doesn’t seem to be the right command.