Blizzard has started a Known Issues list for Season of Discovery Phase 4 PTR. We will continue to update this list with additional known issues for the Phase 4 PTR.
We are working to resolve that issue now. It may be some time as we’ll potentially need a new build to resolve it.
Thanks for your patience.
Update: This has been resolved. Any PTR characters missing cloak runes should have them after relogging.
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