Request double-click file to open External Diff not "Open File"

May I request a way to configure SourceTree-Win so that double clicking on a file in the "staged changes/working copy changes pane" opens External Diff rather than opening the file.

When clicking through files on that pane, because the lines are so close together, I am continually mistakenly double-clicking one line instead of selecting the next line. Given the files I am generally inspecting, usually this means a new copy of Visual Studio starts up which I then have to close. This is a major inconvenience with my SourceTree usage.

But if double clicking opened my External Diff, that would not be an inconvenience, as it would support my review workflow.