Default UE4 Merge Tool

Recently, I tested out perforce and it changed the merge tool inside UE4 to p4merge.exe. How do I change it back to the default one?

Thanks,
Dirt

Ok so it turns out “p4merge.exe” is the default merge tool. However, when I try to diff against depot, I get the error: “The currently set diff tool ‘p4merge.exe’ could not be run. Would you like to set a new diff tool?” And when I try to merge, The engine crashes with this call stack: Assertion failed: Revision.IsValid() [File:D:\Build\++UE4+Release-4.12+Compile\S - Pastebin.com

I’m getting that same error with my project in 4.12

That’s my version as well. idk how to change it.

I get this error in a project with 4.20.2.

you can choose a 3rd-party diff tool now, ref: Diffing Unreal Assets - Unreal Engine