I’ve Always downloaded the older 2013r3.3 dpkg file for setting up a new Linux system for testing. This allowed the installation of the proper Mime types and a desktop definition file for Linux.
I just noticed that you have removed ALL of the dpkg files for all of the archived releases.
Now that these are gone, could you please create a zip or tarball of .desktop and .mimetype files for Xojo so we don’t have to keep old copies around or handcraft them?