Oh, and there's the mention that Debian packages updates are handled by system's update manager, like it would automatically do it, but the thing is, it actually doesn't, as the good old repository system still works the same, if nothing adds the repository, it won't magically appear.
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So Ubuntu app center can handle the .deb packages installation, but not their update. When you open a newer version of the package it's like "nope, nothing more to do, that one is already installed." :neocat_facepalm:
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