The core is no longer checking the value of
requiredJavaVersion that's stored in
skin.properties, so it's not serving any purpose. Stale values that are still there are just misleading - what really matters is the version of
jAlbum that's required, which implies the
Java version that's available in the bundle. A skin developer shouldn't be compiling things like the UI to any higher version of
Java (and at present, should probably be sticking to
Java 14 as the source/binary).
The field also needs to be removed from the skin properties editor (ALT-S). Invoking the editor and saving the file results in a saved value of 1.5.
The skin properties editor could use some refreshing (missing fields), but since a user should never be tinkering with those settings, further refinement is a
very low priority. I use it only to bump the last modified date. For anything else, I just open it in a text editor.