When editing categories on (R) transactions, saved transaction is a new transaction not an edit.
My wife had ~20 orders on her Amazon acct via credit card (CC). Her CC transactions download as Amazon with usually the wrong category but since the amounts are correct, Quicken auto-reconciles the transactions. I go back later, delete the incorrect category and resave the transaction uncategorized. I then search All Transactions for Uncategorized Transactions with Payee Amazon. I then take the search list and enter the correct categories. When I try to save the edited transaction, Quicken asked if I want to change a (R) transaction. When I chose SAVE, Quicken didn't edit the current transaction, it added a NEW transaction correctly edited. Not realizing what initially happened, I tried re-editing the same transaction and Quicken added a 2nd copy to the register. I left my uncategorized transaction list and returned to the register when I saw the original transaction, still uncategorized, plus the two correctly edited and saved transactions. I was able to just delete the original plus one copy to correct the register but Quicken shouldn't have entered NEW transactions. Sorry, but I didn't know where to post a bug report.