Paid builds. You get Access to the source code but you can either build yourself or pay a small amount to have a packaged built and updated whenever.
I also like the twice a year nag screen thunderbird or Wikipedia uses (KDE was right to start doing it too, in my books).
I don’t believe a small donate button in the “about” section of the settings screen is of any use.
You know, games can be great tabletop too, strategic, tactical, RPG, it’s all there + you get to meet people you wouldn’t have met IRL because, like online gaming, it unites people from different walks of life. Great friendships are regularly made around gaming boards and those friends don’t need software to talk too. Yes I know, some games require figurine armies but you can always find someone who’ll be happy to lend you an army for a game and there are whole second hand armies sold.