Running the latest version.
In your example there are a few optional parameters:
Diff2Html.html(this.diffs, {
drawFileList: true,
matching: 'lines',
outputFormat: 'side-by-side',
});
But the types are missing for these in the interface 'Diff2HtmlConfig'.
I've manually added (fileListToggle and matching) so my typescript doesn't complain.
fileListToggle?: boolean;
matching?: string;