I use WinMerge as my external diff tool but it only supports 2-way merges.
Now, from the resolve conflicts screen when I click [Tool Resolve] in the upper section it correctly runs KDIFF in 3-way merge mode. This is as expected.
But from the same screen when I click [3-Way Diff] in the bottom section, it runs WinMerge in 2-way mode, not KDIFF. That doesn't seem correct.