Just a FYI, ChromeOS 73.0.3680.0 is currently rolling out to the Dev Channel and carries a nasty surprise. It appears to delete anything stored in your Downloads Folder without warning after installing it. Please backup your Downloads folder to Google Drive or an external flash drive prior to rebooting. This file deletion bug does not seem to impact anything outside of the Downloads folder including Crostini or Android files. It also does not impact any other files stored in folders outside of your Downloads directory.
Update : Method to recover your Downloads Files