Blizzard has posted new patch notes for Phase 2 of the Dragonflight Pre-Expansion coming with the next weekly reset, which includes merging a number of changes from beta onto the live servers! In addition to many spell and tuning changes, one important user interface and accessibility update is the addition of a new conditional allowing macros to check for known talents!
NEW MACRO CONDITIONAL: KNOWN
Use to check for a talent’s learned status. Works with names and spell IDs.