The Linux Development Environment for Chrome OS will be out of beta with the upcoming Chrome OS 91 update. Google announced this in a Chrome OS keynote. With that, Chromebooks get the first stable version of Linux apps.
Emilie Roberts, developer advocate from Google, said in the keynote that a number of Linux improvements have been added to Chrome OS, such as better stability, configurable port forwarding and improved USB support. Linux Development Environment is also getting a new terminal app.
Another important feature is that the Linux container will now be updated at the same time as a new update to Chrome OS. Now it can take days for the Linux container to get an update after a new update to Chrome OS.
Linux is still an optional feature on Chromebooks, which users have to turn on themselves, and it takes up quite a bit of disk space. Google states that Linux on Chromebooks is primarily intended for developers, but it is also a way to run native applications on Chromebooks instead of web applications or Android applications, such as LibreOffice or GIMP.