Google has released Chrome OS update 91.0.4472.165, which has a bug that prevents you from signing in after a reboot. Some users have experienced a boot loop that prevents the login screen from appearing, or if it does, prevents them from logging in with their account. In hot pursuit, Chrome OS 91.0.4472.167 has been released fixing the issue.
Users who have already installed the first update, but have not yet rebooted the device (the update is activated after a reboot), are advised to urgently bring their system to version 91.0.4472.167. If a problematic update is installed and the entrance is blocked, it is recommended to leave the device turned on for a while and wait until the new update is automatically downloaded. As a fallback, you can try to force the update through guest login.
For users whose system freezes before reaching the login screen and the automatic installation of a new update does not work, it is recommended to press the combination Ctrl + Alt + Shift + R twice and use the factory reset mode (Powerwash) or the system rollback function to the previous version via USB (Revert ), but in both modes the user's local data is deleted. If you fail to call the Powerwash mode, you will need to put the device into developer mode with a reset to its original state.
One user reviewed the fix and came to the conclusion that the reason for blocking the login was a typo, due to which a single β&β character was missing from the conditional statement used to check the type of keys. If (key_data.has_value() && !key_data->label().empty()) { was replaced with if (key_data.has_value() & !key_data->label().empty()) {
Accordingly, if the call to keydata.hasvalue() returned "false", then an exception occurred due to an attempt to access a missing structure.
Source: opennet.ru