Support for dynamic Sparkle feeds

[decodism]

It seems that some applications using Sparkle provide their feed url dynamically through the feedURLStringForUpdater function. Perhaps it would be useful to create a database of these urls for these applications.

Application example: org.tempel.findanyfile -> https://findanyfile.app/appcast2.php

[Tatsh]

It may be possible to dlopen() the binary and call that method directly instead.

A database of URLs has a significant chance of being out of date.

[mangerlahn]

What I definitely don't want to do is to host a server where each instance of Latest requests version information. I don't want to be responsible for maintaining a server that Latest relies on. Also, there are quite some privacy implications here.

Something that might work would be a repository on something like GitHub that acts as the knowledge base for dynamic URLs. That way people can contribute and update URLs. Latest would be able to fetch that list on a regular basis. However all of that requires some planning and proper setup. It would be great to support more apps that way. If an URL goes outdated, then we have the same situation as we have now, the app will appear as unsupported.