There's zips I download from some sites that are wrongly named as .7z or .tar but they're actually .rar files. 7zip is able to recognize this and fall back to the correct file type, but the Opus' unzipper does not seem to know how to handle that (it says the archive is invalid or damaged). Is there a way Opus could handle this properly? Perhaps a naive approach could be to give a list of extensions to try if the extractor fails.
Not easily. We need to know which handler to send each archive type to before the file is opened. (And something is seriously wrong at the source if they're switching extensions to the wrong ones after creating their archives.)
It would be fairly easy to write a script which corrects the filenames after they are downloaded, though.
If it's too much trouble then I guess never mind. I just figured since 7zip does it it could be a not complicated thing to implement.
Feel free to close this thread.