Get Design View back on SharePoint 2013 (woohoo!)

Want to use Design View on a 2013 site? Well, now you can.

With a Fiddler HTTP function we can adjust the server response to say “14” instead of “15” and open any SharePoint 2013 site with SharePoint Designer 2010 to have access to classic Design View. Obviously there are downsides to this approach (not formally supported), but it also can be useful in many scenarios. Check it out and please leave a comment if you find this helpful.

Instructions

Download Fiddler http://www.telerik.com/fiddler
Download SP Designer 2010 http://www.microsoft.com/en-us/download/details.aspx?id=16573
Launch Fiddler, press Ctrl + R, and update the Custom Rules JS file with the code below
Launch SP Designer 2010 and open site URL
Have fun!

Fiddler

You need to add Custom Rules to Fiddler. There are two options:

Download CustomRules.JS with custom logic
Copy the below code and add to your local CustomRules.JS file in the function OnBeforeResponse(oSession: Session).

// START BLOG POST from @spjeff 
// https://www.spjeff.com/2014/05/08/get-design-view-back-on-sharepoint-2013-woohoo
//INF
if (oSession.oRequest["User-Agent"] == "Mozilla/4.0 (compatible; MS FrontPage 14.0)" &&
	oSession.PathAndQuery == "/_vti_inf.html") {
	// Remove any compression or chunking
    oSession.utilDecodeResponse();
    if (oSession.responseBodyBytes) {
        var oBody = System.Text.Encoding.UTF8.GetString(oSession.responseBodyBytes);
    
        // Replace strings
        oBody = oBody.replace("FPVersion=\"15.00.0.000\"", "FPVersion=\"14.00.0.000\"");
        oSession.utilSetResponseBody(oBody); 
    }
}
//RPC
if (oSession.oRequest["User-Agent"] == "MSFrontPage/14.0" &&
	oSession.PathAndQuery == "/_vti_bin/shtml.dll/_vti_rpc") {
	// Remove any compression or chunking
    oSession.utilDecodeResponse();
    if (oSession.responseBodyBytes) {
        var oBody = System.Text.Encoding.UTF8.GetString(oSession.responseBodyBytes);
    
        // Replace strings
        oBody = oBody.replace("major ver=15", "major ver=14");
        oSession.utilSetResponseBody(oBody); 
    }
}
 
//AUTHOR
var suffix = "/_vti_bin/_vti_aut/author.dll";
if (oSession.oRequest["User-Agent"] == "MSFrontPage/14.0" &&
	oSession.PathAndQuery.indexOf(suffix, oSession.PathAndQuery.length - suffix.length) !== -1) {
    if (oSession.responseBodyBytes) {
        // Remove any compression or chunking
        oSession.utilDecodeResponse();
        var oBody = System.Text.Encoding.UTF8.GetString(oSession.responseBodyBytes);
    
        // Replace strings
        oBody = oBody.replace("SR|15.0", "
SR|14.0");
        oSession.utilSetResponseBody(oBody); 
    }
}
// END BLOG POST

Use Cases

Support upgraded 2010 sites. If you developed with SP Designer 2010, you might need Design View to support sites after upgrade to 2013.
New HTML and CSS creation. WYSIWYG can be great for making simple files to support new JavaScript development.
DataFormWebPart . Create blank ASPX page, add the DataFormWebPart and Conditional Formatting with WYSIWYG, then copy finished <DataFormWebPart> code tag into a 2013 native ASPX page.

Notes

Non intrusive approach. Fiddler runs local on the developer’s machine. No server changes or changes for end users.
This doesn’t give you Design View of any native 2013 ASPX page. Those are fundamentally different with new Minimal Download Strategy async load, new master page, and other stuff so it just shows a gray background.
Not formally supported.
Cool way to support SP2010 upgraded sites.

References