Download the extension package to your computer.
Download signedtext-helper.zipOpen a new tab in Chrome and go to:
For security reasons, the browser does not allow this page to be opened directly via a link. Copy the address, open a new tab (Ctrl+T) and paste it into the address bar (Ctrl+V).
In the top right corner of the extensions page, enable the Developer mode switch.
Drag the downloaded signedtext-helper.zip file directly into the browser window on the extensions page.
Alternatively: Unzip the file and use the "Load unpacked" button.
Click the puzzle piece icon (Extensions) in the browser toolbar, and click the pin icon next to SignedText Helper to keep it visible.
The extension is now active. Return to the SignedText page and refresh it (F5) / (Ctrl+R).