Your Questions

Are there any client libraries are available??

The API is a REST based API accessible by most, if not all web technologies.
Currently, there is only a .Net core client library available.
Code on github:

Does MediaMarkup use any client plugins?

No, the viewer uses html 5 features and does not require any specific plugins. Mediamarkup is built for modern browsers, please ensure you are using the latest version of your browser.
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