SignatureSatori: Gmail Signature Remover Beta

One-click Signature remover. Stop losing time while selecting and deleting your signature from emails to colleagues or friends. Just click on the button and signature will be removed from your message.

This extension is brought to you by SignatureSatori (https://www.signaturesatori.com) - central signature management for Google Apps.

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How to get rid of the double dash?
Go to Gmail settings: https://mail.google.com/mail/u/0/#settings/general, scroll down to Signature and right under your signature tick the checkbox: "Insert this signature before quoted text in replies and remove the "--" line that precedes it".