https://developer.apple.com/forums/thread/667739?answerId=670780022#670780022
Worked for me.
At the end it says "9. Proceed with Step 3, including reboot", but there is no step 3 so I did a
'reboot' from the terminal and
once booted did an install from a freshly downloaded "GoogleDrive.dmg" (was version 47.0.17.0).
Then approved the extension in the preferences.
Chose "Not now" for the reboot.
Closed Preferences.
Rebooted from the Apple menu.
hjmunro
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