When clicked on a JSON file that has changes, SourceTree freezes

I need to work with JSON files and whether they're small or big in size, when I click on them to see the difference on the SourceTree GUI it just freezes. If the JSON file is relatively small, the app then works after a few minutes but if the JSON is larger than 1MB then the app doesn't come back alive, and I need to shut it down via the control panel and re-launch it. 

Same thing happens on the staged/unstaged files as well as stashed ones. If you click on a stash that has a JSON change in it, the app will freeze and crash.