🐛 Affected by git's diff config

[amb007]

In ~/.gitconfig (the only config file) I have

[diff]
...
external=difft

If I cd to /tmp, I expect delta to know it's not a git repo. However, looking at strace output of delta file1 file2, it seems that delta (v0.18.2) gets to page the output of difft. When I comment out the external=difft line, I see in strace output diff -git... and the expected delta output.
What exactly is going on and is there a way not to use difft without having to comment out the above line?

Thanks,
Alex