First select all groups and
Just use CTRL+E or Cmd+E on mac shortcut - and thats all
You can try also, to convert it to a smart object> Layer > Smart Object > Convert to Smart Object, or just try right click at the name and Convert to Smart Object. That way you will have an embed separated PSB file.
Almost there, but these commands only do one layer at a time, or if select all and then Cmd+E it merges all layers into one layer.
Doesn't take long to Cmd+E individual layers, but would be quicker if I could do all layers at the same - prob not!