Note: You can also disable the extension from the extensions page using the blue switch. Removing obviously deletes all extracted data, while disabling doesn't.
Chrome
...and other Chromium based browsers, including Microsoft Edge.
At the top right, click More MoretoolsExtensions.
On to the extension you want to remove, click Remove.
Confirm by clicking Remove.
Firefox
Click the menu button, click Add-ons and Themes and select Extensions.
Scroll through the list of extensions.
Click the ellipsis (3-dot) icon for the extension you wish to remove and select Remove.