As long as you don't directly work with FLIF, cause tools don't support it, having the file browser's preview-feature work using FLIF would be awesome. This way it doesn't need to store n previews for the supported preview resolutions but could store just a flif of the max preview size per document (psd, jpg, png, svg, pdf) and then, when you seek 3 pages down, the system reads the first kB of each such preview to render it and reads the next kB to improve the images, etc.
Sure, for actual flif files you would not have a separate preview file.
Sure, for actual flif files you would not have a separate preview file.