here in the main hall, they have on royalty-free techno music. the music is being played on a mac (non-free software), in the brave browser (free-ish software). in the dock there are several icons for microsoft and other non-free software.
they have swapped out for another machine running KDE (free software). it is showing a slideshow authored in Google Slides (non-free software), and the browser appeared to be Firefox (free software).
@ariadne Could you please add to the alt text that that this is a photo from fosdem and that the text you mentioned is on a large slide behind a man speaking at a podium? This is helpful context.