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I was able to make a build for Ubuntu 16+ 64bit. The only small issue I've found is Pixel Fireplace can't prevent Ubuntu's sleep settings, so you'll have to adjust them if you don't want the display/computer to sleep while running it. I won't be able to fix this unless Game Maker adds a new function for overriding it. Everything else seems to work fine including dual screen support, but let me know if you find something. Some more details from the GM:S website:

"Ubuntu 16 or later is required. Other distros can usually run the games that GMS2 generates with no issues, but we only state support for Ubuntu, so if you have issues playing games on these other platforms you will need to investigate this yourself. All games are 64bit-only"