It could've been great, but is not. Obviously in the development of this addon is missing the contribution of a UX/UI and a software analyst.
Several issues like:
- the pages do not show in the bookmarks, and that is the only way to export them when reinstalling, wich make it unusable for me.
- tiles are static and non responsive design was used
- the preview is a bad bad idea, it should have been just as an option or button... UI is missing
- tiles cannot be added offline
- slow/useless animation
- unfriendly and unprofessional aspect in the same time
- painfully ugly icon that does not work with any theme...
- trying to promote a certain search engine... they probably paid.
- etc, etc.

It could have been brilliant, I would have paid for a good extension.

So far so good, I like the simplicity of it, but one of the problems is the search engine, it is 2020, no one uses Yahoo so please change to Google or at least give the users an option to choose their preferable search site.

Adding pages as tiles completely blows up the tiles themselves, and it seems like the loaded website spills over the entire start-up screen. Clarification: the speed-dial to be added loads the entire page and so there are overflowing content windows over the speed-dial start page. Where do I provide a screenshot? What I used it on: mixcloud.com as a speed dial tile.

Light and usefull, but despite default firefox search engine is google - speed dial search choose bing

Unable to enter URL with "#" symbol.

There was a bug with netflix on the speed dial. The tile distended and could not be removed despite refreshing and booting. Other than that, it worked fine.