Yeah, I need this because I will shortly need Java 10 / 11. Also, dark theme support is far superior in Photon. For now I have to run two copies of eclipse, but this only works for scala only projects or java8/scala ones. I'll never be able to have one IDE for both Java 9+ and scala without an update. Or a big loss of productivity learning IntelliJ or leaping off into VSCode and hoping for the best.
At this point, I'm thinking this project is dead. The last RC is 9 months old with no release. No support for Photon (or the follow-up that supports Java 11, due soon) is in sight.