Setting up environment variables at login in Whonix 16

Now that Whonix uses gdm3 I’m finding it very difficult to setup environment variables at login because apparently gdm3 doesn’t source .xprofile, .profile, .bash_profile, .zprofile (when using zsh) or .xsessionrc. I know lightdm sources from .xprofile but gdm3 doesn’t (at least it doesn’t in Whonix). Anyone knows how to set environment variables at login in Whonix?