How to integrate CryptoPro myDSS into a web application?

Question

User identification

It is necessary to integrate the ability to sign documents with CEP into the web application.
I'm trying to find the best option.

It is assumed that users will already have a CEP key stored on a flash drive.
I tend to think that you need to tie the CryptoPro CSP + CryptoPro Browser Plugin to the front, but in this scheme, quite a lot of software needs to be installed on the user's computer.

I know that there are various modern solutions, for example, from Kontur based on myDSS. Can it be used for this case, given that the key is qualified and stored by users? If yes, how? Is there any benefit from this at all?