extensions/markdown-language-features/src/languageFeatures/dropIntoEditor.ts/getMdPath
function getMdPath(dir: vscode.Uri | undefined, file: vscode.Uri) {
	if (dir && dir.scheme === file.scheme && dir.authority === file.authority) {
		if (file.scheme === Schemes.file) {
			// On windows, we must use the native `path.resolve` to generate the relative path
			// so that drive-letters are resolved cast insensitively. However we then want to
			// convert back to a posix path to insert in to the document.
			return encodeURI(path.posix.normalize(path.relative(dir.fsPath, file.fsPath)));
		}

		return encodeURI(path.posix.relative(dir.path, file.path));
	}

	return file.toString(false);
}