I have a text file in my repo that tracks recent changes I've made from a user point of view. After editing the file it is marked as changed in the "Unstaged files" list, but when I select it I don't see the changes in the panel next to it. Instead I see a green circle with a check in it next to the file name (Readme.txt).
Selecting lua or any other source files work as expected. Latest SourceTree for Windows (Version 1.6.12.0).