Diffing log output is a great technique for tracking down weird, hard to repro bugs I find - log out as much as you can in a normal session and then in a buggy session, and diff the two, just as you describe.

Have also used this technique to compare build logs when you have a version of a project which will compile and one which doesn’t (eg when trying to integrate a second project into an existing one, or battling CI issues), useful if you aren’t an expert in that particular tool chain especially.

Personally I use VS Code’s diff these days, since they added support for word wrap recently, it’s the easiest to read.