[X2Go-User] How to reduce fonts size?

Hello,

Though I read https://www.mail-archive.com/x2go-user@lists.x2go.org/msg03049.html and when using 'Single application' or 'Published applications', and running Thunderbird (91.1.2) from a 4.1.0.3-5 x2go server running on an Ubuntu 21.10, to my XUbuntu 21.10 desktop, whatever setting I'm trying to use about the DPI has absolutely no effect on the fonts size in the published Thunderbird.

They are significantly bigger, and don't change either when raising nor lowering the DPI setting.

Is this something I could check somewhere in the logs, or does anyone has any advice about it?

Thank you.

-- Nicolas