To properly go under the hood and hack around on a Samsung Chromebook 2, you’ll need to put it into developer mode. Whether using crosh or installing Chromium or other operating systems or just doing some pretty cool stuff, you’ll need to throw the thing into developer mode. Because you have so much control you should leave developer mode off when you’re not hacking around for security purposes.
Note: Before you switch back and forth, know that user accounts will be reset each time you switch.
Now, to enter developer mode, we’ll first go into recovery mode, using the Escape (ESC) and Refresh (F3) buttons on the keyboard when you press the Power button. When the Recovery screen comes up, use Ctrl-D to switch to developer mode and then when prompted, confirm and the device will reboot into developer mode (or dev-mode for the geeky). When you see the boot screen, wait 30 seconds to boot or just hit Control-D.
To switch back to normal mode from developer mode use the crossystem command followed by disable_dev_request and set that to one and then reboot. To make this a shell one-liner:
crossystem disable_dev_request=1; reboot
And that’s it. Happy hackin’!