Case 1: Writing a sensitive email. If you use the Drafts folder on your email server, the email will be automatically saved there and anyone with access to that server has access to that email.
Case 2: You are using Gmail IMAP. Gmail automatically copies deleted emails to the trash folder. This means that if you took your time writing an email, there would be multiple copies of the draft in your Trash folder when you got done. One for each time auto save ran.
If you use the Android Gmail app, then all of these extra copes will also show up in your conversation for that message.
To get around these and similar problems, you can set your Drafts folder for your account to your Local Folders. However, when you want to save a draft on the email server, you then have to manually move the draft from your Local Folders to the Drafts folder in your email account.
This extension automates the process so that you can setup your account to use the Drafts folder on your email server like you normally would, but not have to worry about the auto save feature doing things you don't want.
For further instructions and support, please use the home page and support links to the right.