The title is pretty descriptive of the issue. I have been trying to migrate older computer users over to Linux and have found a number of unusual problems. One of them is that Firefox for Linux seems to lack a feature that exists on Windows: when you open the file upload window, there is no ability to search for the file you want. Instead you have to already know where/what it is, something that can be problematic at times. Is this a known issue? I can't speak for all distros, but at least on Kubuntu it is an issue.