If you wish to disable or remove the Flashissue Chrome Clipper extension. Here's what to do.
Step 1: Close the Gmail tab
Step 2: Right click the icon on Chrome
Open Chrome and using you mouse right click the scissor icon on your browser bar.
Step 3: Click Manage
Step 4: Remove the check-box on the extension setting screen.
Click the check mark to disable the extension.
You'll end up seeing this:
Note: Alternatively, you can also access the extension screen from the Chrome menu
Chrome > Preferences > Extensions.