opensheetmusicdisplay/opensheetmusicdisplay

Function ajax has 29 lines of code (exceeds 25 allowed). Consider refactoring.

Open

    public static ajax(url: string, timeout: number = 9000): Promise<string> {
        let xhttp: XMLHttpRequest;
        const mimeType: string = url.indexOf(".mxl") > -1 ? "text/plain; charset=x-user-defined" : "application/xml";
        if (XMLHttpRequest) {
            xhttp = new XMLHttpRequest();