I am not sure about 1.1.8 since I am using version 1.9 / 2.0 release, but I believe that you can left-click on changeet1, right-click on revision 3 and select visual Diff. This should open your optional comparison tool and show only the difference between the two versions.
When I did this in a new turtle, he opened BeyondCompare in directory comparison mode, with revision1 on one side and revision2 on the other.
Mikezx6r
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