Automatically removes formatting from your clipboard when you use normal copy paste [Ctrl+c]. If you need to keep the formatting, you can toggle it on and off by right clicking something you've selected/highlighted and pressing 'Get format next copy'. On the next copy you do, it will keep the formatting. Then it will reset back to the default plaintext setting for future copying.
simple and robust.
The extension will not be active on tabs/windows that were already open prior to the installation. Try refreshing the tabs or open a new one to test it out.