Hi @mediapuck! Thanks for reaching out. There is still time for developers to port their extensions to the WebExtensions API in time for the Firefox 57 release, and developers will still be able to migrate even after the release.
According to their website, it looks like the developers of FVD Speed Dial are planning to release a compatible version of their extension soon. When they update the code, you should automatically get the new version.
For more information about what to expect for add-ons with the Firefox 57 release, how to find compatible extensions, and how to find replacements for legacy extensions, please feel free to take a look at the article on SUMO and Frequently Asked Questions.