Found a bug

Hello, we found a bug on your application today... It appears if you add someone to one of your spreadsheet creations and give them full permissions, they can add things to the sheet by using the add tab... However, unlike the owner, the person granted access does not have an add button on the spreadsheet on the spreadsheet tab, which we think is the easiest way to add to the spreadsheet for our needs. Could you look into this? Thank you
hawkhead99