--- a/toolkit/modules/NewTabUtils.jsm
+++ b/toolkit/modules/NewTabUtils.jsm
@@ -921,50 +921,55 @@ var ActivityStreamProvider = {
   },
 
   /**
    * Computes favicon data for each url in a set of links
    *
    * @param {Array} links
    *          an array containing objects without favicon data or mimeTypes yet
    *
-   * @returns {Promise} Returns a promise with the array of links with favicon data,
-   *                    mimeType, and byte array length
+   * @returns {Promise} Returns a promise with the array of links with the largest
+   *                    favicon available (as a byte array), mimeType, byte array
+   *                    length, and favicon size (width)
    */
   async _addFavicons(aLinks) {
     if (aLinks.length) {
       // Each link in the array needs a favicon for it's page - so we fire off
       // a promise for each link to compute the favicon data and attach it back
       // to the original link object. We must wait until all favicons for
       // the array of links are computed before returning
       await Promise.all(aLinks.map(link => new Promise(resolve => {
         return PlacesUtils.favicons.getFaviconDataForPage(
             Services.io.newURI(link.url),
-            (iconuri, len, data, mime) => {
+            (iconuri, len, data, mime, size) => {
               // Due to the asynchronous behaviour of inserting a favicon into
               // moz_favicons, the data may not be available to us just yet,
               // since we listen on a history entry being inserted. As a result,
               // we don't want to throw if the icon uri is not here yet, we
               // just want to resolve on an empty favicon. Activity Stream
               // knows how to handle null favicons
               if (!iconuri) {
                 link.favicon = null;
                 link.mimeType = null;
+                link.faviconSize = null;
               } else {
                 link.favicon = data;
                 link.mimeType = mime;
                 link.faviconLength = len;
+                link.faviconSize = size;
               }
               return resolve(link);
-            });
+            },
+            0); // preferredWidth: get the biggest width available
         }).catch(() => {
           // If something goes wrong - that's ok - just return a null favicon
           // without rejecting the entire Promise.all
           link.favicon = null;
           link.mimeType = null;
+          link.faviconSize = null;
           return link;
         })
       ));
     }
     return aLinks;
   },
 
   /**

--- a/toolkit/modules/tests/xpcshell/test_NewTabUtils.js
+++ b/toolkit/modules/tests/xpcshell/test_NewTabUtils.js
@@ -338,18 +338,20 @@ add_task(async function addFavicons() {
   await setUpActivityStreamTest();
   let provider = NewTabUtils.activityStreamProvider;
 
   // start by passing in a bad uri and check that we get a null favicon back
   let links = [{url: "mozilla.com"}];
   await provider._addFavicons(links);
   Assert.equal(links[0].favicon, null, "Got a null favicon because we passed in a bad url");
   Assert.equal(links[0].mimeType, null, "Got a null mime type because we passed in a bad url");
+  Assert.equal(links[0].faviconSize, null, "Got a null favicon size because we passed in a bad url");
 
   // now fix the url and try again - this time we get good favicon data back
+  // a 1x1 favicon as a data URI of mime type image/png
   links[0].url = "https://mozilla.com";
   let base64URL = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAA" +
     "AAAA6fptVAAAACklEQVQI12NgAAAAAgAB4iG8MwAAAABJRU5ErkJggg==";
 
   let visit = [
     {uri: links[0].url, visitDate: timeDaysAgo(0), transition: PlacesUtils.history.TRANSITION_TYPED}
   ];
   await PlacesTestUtils.addVisits(visit);
@@ -357,16 +359,17 @@ add_task(async function addFavicons() {
   let faviconData = new Map();
   faviconData.set("https://mozilla.com", base64URL);
   await PlacesTestUtils.addFavicons(faviconData);
 
   await provider._addFavicons(links);
   Assert.equal(links[0].mimeType, "image/png", "Got the right mime type before deleting it");
   Assert.equal(links[0].faviconLength, links[0].favicon.length, "Got the right length for the byte array");
   Assert.equal(provider._faviconBytesToDataURI(links)[0].favicon, base64URL, "Got the right favicon");
+  Assert.equal(links[0].faviconSize, 1, "Got the right favicon size (width and height of favicon)");
 });
 
 add_task(async function getHighlights() {
   const addMetadata = url => PlacesUtils.history.update({
     description: "desc",
     previewImageURL: "https://image/",
     url
   });