@mariatta @glyph the display adaptor can be a problem - for example Apple devices are not common on South Africa, so only 1 or 2 presentations a year at PyConZA use one. None of the organisers have an Apple so the first time in recent years that someone needed a specific adaptor we had to scrabble to borrow one from another attendee as we didn't know the one we had wouldn't do. We now specify HDMI input and make it clear presenters need to bring whatever they need to emit HDMI.