Enable annotation layer (text and link)

[zeecorleone]

How can the annotation layer be enabled in pdf.js being used? When try something like following:

 var promise = page.getAnnotations().then(function (annotationsData) {
        viewport = viewport.clone({
            dontFlip: true
        });

        for (var i = 0; i < annotationsData.length; i++) {
            var data = annotationsData[i];
            var annotation = PDFJS.Annotation.fromData(data);
            if (!annotation || !annotation.hasHtml()) {
                continue;
            }
            //. . . . code continues

This won't work, as it will break at PDFJS.Annotation.fromData(data) because PDFJS is no more available from version 2.0 onwards.

What I'm trying to do:
My goal is to enable links in pdf. for example, there are some links that point to a specific page within the same pdf document. Currently they aren't enabled. I tried to search and found that it could be enabled by enabling the annotation layer. But all examples I found related to enabling annotation layer are using PDFJS instance. Any help would be appreciated.