As Java 6 is in end of life status for a long time, i think it is safe to drop Java 6 support in Spark completely. I think it is sufficient to have Spark 2.6.3 to still support it, but all newer version should work with Java 7 and don't have hooks to Java 6 anymore. Support for Java 6 is creating issues like described in the forum thread linked to this ticket. If users have Java 6 on their system (they need it for some reason), then Spark will use that older Java no matter the fact that it has Java 7 bundled. So old java bugs are crawling back (focus stealing, tray icon distortion and other issues). We then get bug reports about such issues which can't be fixed any way other than dropping Java 6 hooks.