remove more XXX notes, add stricter team invite link content validation

www/common/common-ui-elements.js

@@ -3616,7 +3616,7 @@ define([
                     });
 
                     var displayName = UI.getDisplayName(data.name);
-                    common.displayAvatar($(avatar), data.avatar, displayName); // XXX
+                    common.displayAvatar($(avatar), data.avatar, displayName);
                     return h('span.cp-mentions', {
                         'data-curve': data.curvePublic,
                         'data-notifications': data.notifications,

www/profile/inner.js

@@ -348,7 +348,7 @@ define([
         if (!val) {
             $('<img>', {
                 src: '/customize/images/avatar.png',
-                title: Messages.profile_avatar, // XXX
+                title: Messages.profile_defaultAlt,
                 alt: Messages.profile_defaultAlt,
             }).appendTo($span);
             return;
@@ -391,7 +391,7 @@ define([
                 }, function () {
                     sframeChan.query("Q_PROFILE_AVATAR_ADD", data.url, function (err, err2) {
                         if (err || err2) { return void UI.log(err || err2); }
-                        displayAvatar(data.url); // XXX add "Profile picture"
+                        displayAvatar(data.url);
                     });
                 });
             };

www/teams/inner.js

@@ -1099,8 +1099,8 @@ define([
             if (!val) {
                 var $img = $('<img>', {
                     src: '/customize/images/avatar.png',
-                    title: Messages.profile_avatar, // XXX
+                    title: Messages.profile_defaultAlt,
-                    alt: 'Avatar'
+                    alt: Messages.profile_defaultAlt,
                 });
                 var mt = h('media-tag', $img[0]);
                 $avatar.append(mt);
@@ -1323,16 +1323,23 @@ define([
             });
         };
 
+        var isValidInvitationLinkContent = function (json) {
+            if (!json) { return false; }
+            if (json.error || !Object.keys(json).length) { return false; }
+            if (!json.author) { return false; }
+            return true;
+        };
+
         nThen(function (waitFor) {
             // Get preview content.
             sframeChan.query('Q_ANON_GET_PREVIEW_CONTENT', { seeds: seeds }, waitFor(function (err, json) {
-                if (json && (json.error || !Object.keys(json).length)) { // XXX team invite links are triggering this every time for me?
+                if (!isValidInvitationLinkContent(json)) {
                     $(errorBlock).text(Messages.team_inviteInvalidLinkError).show();
                     waitFor.abort();
                     $div.empty();
                     return;
                 }
-                // XXX nothing guarantees that author, teamName, or message exist in json
+                // FIXME nothing guarantees that teamName or author.displayName exist in json
                 $div.empty();
                 $div.append(h('div.cp-teams-invite-from', [
                     Messages.team_inviteFrom,