I have a gateway backup and I want to add other projects to it. Is there a way to find out what version of ignition the gateway was saved as so I can make sure the new projects are at the same version as the existing ones?
Gateway backups are ZIP files. At the root level, they contain a
backupinfo.xml file with the information you desire.
What if we only have the .gwbk file?
Different extension, still a zip file.
This info is nicely presented for you in Kindling, by the way.