With the version 2.2.1 update to GameMaker Studio 2, a new Beta Channel has been added to Preferences.
This channel is for people who want to get bug fixes or new features sooner and in exchange are willing to risk encountering bugs or issues associated with a version that has not completed testing. We also ask of these users that they do report these issues as soon as they see them so that by the time the "Stable" release is made these issues have been fixed.
To stress that point: the beta channel version of GameMaker Studio 2 may contain bugs that could corrupt your projects. It may also introduce project structure changes which, whilst being completely safe and correct, block you from taking that project back into earlier GMS2 versions or sharing the project with others who are not using the beta version.
Accordingly, the Beta Channel opt-in will not be available for minors, Educational users who log in using seats, or anyone using the free Trial version. We would also caution users of shared computers from opting-in, as the setting is for the GMS2 install, not per-user.
It is also currently not available on Steam (we will review this for possible inclusion in a later release). For our Steam users, your YoYo Account is valid for the non-Steam version as well, so feel free to install and use that to take part in the beta.
You will need to follow the instructions and download the beta IDE installer from this helpdesk article: Opting Into The GameMaker Studio 2 Beta Channel
As above, if your account is not eligible for the beta system, whilst the installer will work for you, you will be unable to get the correct runtimes. So please don't use the installer if you're a Trial user, below the age of majority in your territory, or an educational user.
Version 2.2.1 is our biggest ever bugfix release, thanks to our ongoing consolidation. Including, updated macOS IDE's Mono version, in-game performance optimizations, Android adaptive icons support, custom maps for gamepads and a huge amount of HTML5 fixes.
Check out all the details here:
Beta IDE Release Notes: http://gms.yoyogames.com/ReleaseNotes-Beta.html
Beta Runtime Release Notes: http://gms.yoyogames.com/release-notes-runtime-Beta.html