Djvu certainly may fall out of use some day, but I think you are greatly underestimating how popular the format is if you really think think there won't be prog

Djvu certainly may fall out of use some day, but I think you are greatly underestimating how popular the format is if you really think think there won't be programs around to read it. It's not an obscure format, and there are widely used open source libraries to do so.