An UPGRADES file defines the purchasable upgrades for Bloons Tower Defense games. These files are stored in a game’s UpgradeDefinitions directory. Find an UPGRADE file in Windows File Explorer. Double click to launch the application. If you get an error, you should look for an application which can open the file. Alternatively, associate the UPGRADE extension to software in the Windows Registry. Learn about the UPG file extension and software to open .upg files. We also have free online UPG tools to view, edit, convert, merge, split and compare UPG files without installing anything.
This shows the output after removing an invalid file and upgrading an Ubuntu 16.10 system. I tested another machine with the same system. It has the same behavior. So it is probably the package update causing this.
Sony uses UPG files for Walkman firmware upgrades. Philips uses them for TV firmware. Although these files have the same extension, they may not be in the same format. Other manufacturers distributing firmware as UPG files include Epson.
The moz-upgrade extension is for Mozilla Firefox browser updates. The firefox.exe.moz-upgrade file is used by the update service. These files are probably not meant to be accessed by users. MOZ-UPGRADE files are supported on Windows devices. Mozilla Firefox is the most commonly used program for working with MOZ-UPGRADE files.