If the Scheduled Transaction Editor is open ("Scheduled Transactions" tab) and the user selects Actions->Scheduled Transactions->Scheduled Transaction Editor, an additional Scheduled Transactions tab will be opened.  An indefinite number of these duplicate tabs will be opened if the user keeps selecting "Scheduled Transaction Editor" from the Actions menu in a similar way.

This behavior is inconsistent with account tabs.  When the user opens the register for an account from the account tree, focus will be given to the corresponding tab if the register for that account is already open in a tab.  The behavior should be the same for anything that opens in a tab like this.

This is only a minor nuisance.  I noticed it after I was switching back and forth between a scheduled transaction and a transaction in a register tab.  I had forgotten I had left the scheduled transaction editor open and had returned to the menu item to open it.  In the end I had three duplicate scheduled transaction editor tabs open, which is silly.