Revision history is limited to 100 revisions for non-native files.
When creating a recurring event with no end condition, the maximum amount of events created will be 730.
When a quarantine group is not specified and notifications are enabled, the notification email will be sent to all superadmins. (Still working to confirm - may be a bug)
If you right-click to disable spellcheck, you cannot re-enable it in settings (i.e chrome://settings/languages). You have to right click again and select the option to re enable. Video here
When clicking 'Move-to' for a folder to a Team Drive, the fileID's of the individual files inside the folder will keep their value. However, the folder ID value will change, thus breaking any hyperlinks that linked to that specific folder. (i.e. you have a document that has links to folders)
There is no known limit to the amount of labels that you can have in Gmail. Adding labels will simply decrease performance until Gmail becomes functionally unuseable. Google recommends not going over 500, and we recommend staying well under that.