I am running
Xcode 7 and
When I select a conflicted file and
Launch an external merge tool, there is a window that appears very briefly... and then nothing happens.
I tried (see this help page)
sudo ln -s /Developer/usr/bin/opendiff /usr/bin/opendiff but it did not work (I got the message
ln: /usr/bin/opendiff: File exists).
What should I do?
Here is a picture of the window that briefly appears.
Here are the SourceTree preferences: