For all Creative Cloud versions we recommend using the free DMXzone Extension Manager. It does not rely on Adobe CC internals to install the extension and as such may not be affected by any Adobe CC internal issues or database corruptions. We have fully tested this extension manager and it will work with all of our extensions.
If the extensions do not appear in Dreamweaver it indicates a file corruption in the Dreamweaver configs, specifically menus.xml and insertbar.xml. The latest update to the Adobe Creative Cloud app can cause syntax corruption in those two files. It's an Adobe CC issue which we no control over, hopefully they will fix it soon.
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