Finally! You can install the latest Arduino IDE and upload code to an Arduino on a Chrome OS device!!! I've documented the entire process. It's hacky, but works well after the install. **
How to install Arduino on Chromebook | Chrome Ready
Arduino Create comes to Chrome OS devices! | Arduino Blog
Installing the Arduino IDE on a Chromebook by James Finch | TPT
GitHub - spaceneedle/Chromeduino: Arduino IDE and programmer (avrchick) for ChromeOS/Chrome Browser
ChromeBook とArduino IDE 2.0 で M5Stackの開発をする
UNO WiFi Rev 2 Chromebook Setup | Arduino Documentation
Arduino for Chromebooks - ArduinoInfo
Arduino Cloud for Chromebook – Apps bei Google Play
ChromebookからArduino に書き込む - Qiita
Lantau kilowatt counter: Arduino IDE on Chromebook via Crouton
How to install Arduino IDE on your Chromebook | by Ethan A | Medium