I have noticed many times, that when I manually enter a transaction using a previously entered transaction Quicken suggested as I entered the Payee field information, the CLR field is also copied into the new, just being entered, transaction. This should not happen as it is almost impossible to reconcile a transaction before it is entered.
One of the Community members in Classic Quicken said it never happens to him.
It happens to me in both versions so it is still in the Mac beta version 7.8.0.
If you cannot reproduce it, I can show it happening on a screen share.