Signer.Digital Digital Signature, PKI

The Signer.Digital extension for Firefox does not function... After installing, enabling and pinning it to my Firefox Browser, when I click on the Signer.Digital extension icon, it always gives the message "Signer.Digital Extension not detected in your browser. Take a moment to review the requirements..!!". The rest of the page talks of how to install the browser extensions. If I skip this and go on to PDF Signing, it works till you add the location for entering the signature. When it tries to actually add the signature, it gives an error that Signer.Digital Windows extension is not found, and asks to download and run the Signer.Digital.*.msi file again - which was already done long before. Repeating the installation of the .msi and the whole process above, does not solve the problem. Same issue occurs again !! All this is while the Signer.digital extension for Chrome and Edge browsers are working fine on my device at the same time. So, the Signer.digital extension for Firefox is clearly broken... Please fix this...