Edit Menu

Undo Reverses (one at a time) a series of editing actions
Redo Reverses (one at a time) a series of Undo actions

Cut Selected lines as removed Copies the selected text to the clipboard and Marks the lines as Removed.
Copy Copies the current selection to the clipboard

Text can be selected by pressing and holding down the mouse button within a difference or merge view window. Then, moving the mouse to highlight the desired text.

Paste Pastes the contents of the clipboard at the insert point in either merge text Or ComparEdit's 1st or 2nd text
Mark Selected lines as removed/restored Marks the selected lines as Removed(displayed with StrikeThru). Or, for lines marked as Removed, Restores the lines.
Flip Flips the order of 1st/2nd lines in the current Merge change.

Replace Change from 2nd in 1st Copies the lines of the current change from the 2nd text to the 1st text, replacing the existing lines in the 1st text.
Replace Change from 1st in 2nd Copies the lines of the current change from the 1st text to the 2nd text, replacing the existing lines in the 2nd text.

Select All Together View Selects all the contents in the Together View.
Select All 1st View Selects all the contents in the 1st File View.
Select All 2nd View Selects all the contents in the 2nd File View.