Just subscribed to CC Photography package (previously used PS CS5.1, BR 5.1 and LR 5), as I recently upgraded my camera.
I'm using LR Classic CC for RAW files, but when I go on to "edit in PS CC" option, it opens CS 5.1 instead, then nothing happens as obviously my version of ACR is too old. Same thing happens in LR CC.
It navigates from BR CC to PS CC no problem.
Sorry that the "Edit in Photoshop" command in Lightroom Classic CC and Lightroom CC does not work. Could you please take a look at the steps mentioned in this article 'Edit In Photoshop' command missing and let us know if that helps.
Thanks Akash. The prefs option solved it. Also thanks as I had been wondering where Apple had hidden the library ;-)
Thanks for the update. Glad to know you got it working.