Adobe dropped support for their extension manager.  You can use one of the free third party solutions like:
https://www.projectseven.com/products/ex-man/info.htm
 
 7/14/2020 1:25 pmRay BorduinWebAssist
7/14/2020 1:25 pmRay BorduinWebAssist
        Adobe dropped support for their extension manager.  You can use one of the free third party solutions like:
https://www.projectseven.com/products/ex-man/info.htm
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.