cli: document diff format
@@ -97,6 +97,13 @@ Which elements can be colored is not yet documented, but see
the [default color configuration](https://github.com/martinvonz/jj/blob/main/src/config/colors.toml)
for some examples of what's possible.
+### Diff format
+
+```toml
+# Possible values: "color-words" (default), "git", "summary"
+ui.diff.format = "git"
+```
+
### Graph style
```toml
