Great concept, and this addon does work, but like others have said, it badly needs some customization options, as it hardly has any avail.
Should be able to select desired time frame of when preview opens on all links, or if do not want preview to open. This app opens all over the pages,any time just briefly scroll over links, so you have to keep closing undesired previews, which gets very frustrating to deal with every day, so had to Disable this addon for now. It also does not work on many links still.
Also, should be able to select desired preview window size, and quickly Rt or Lt Click out of preview. Great app, but needs improving, more custom options asap.