--- a/toolkit/content/aboutTelemetry.js
+++ b/toolkit/content/aboutTelemetry.js
@@ -319,16 +319,43 @@ let StackRenderer = {
         div.appendChild(document.createTextNode(symbol));
         div.appendChild(document.createElement("br"));
       }
       div.appendChild(document.createElement("br"));
     }
   }
 };
 
+function SymbolicationRequest(aPrefix, aRenderHeader, aMemoryMap, aStacks) {
+  this.prefix = aPrefix;
+  this.renderHeader = aRenderHeader;
+  this.memoryMap = aMemoryMap;
+  this.stacks = aStacks;
+}
+SymbolicationRequest.prototype.handleSymbolResponse = function() {
+  StackRenderer.renderSymbolicatedStacks(this.prefix, this.symbolRequest,
+                                         this.renderHeader);
+};
+SymbolicationRequest.prototype.fetchSymbols = function() {
+  let symbolServerURI =
+    getPref(PREF_SYMBOL_SERVER_URI, DEFAULT_SYMBOL_SERVER_URI);
+  let request = {"memoryMap" : this.memoryMap, "stacks" : this.stacks,
+                 "version" : 3};
+  let requestJSON = JSON.stringify(request);
+
+  this.symbolRequest = XMLHttpRequest();
+  this.symbolRequest.open("POST", symbolServerURI, true);
+  this.symbolRequest.setRequestHeader("Content-type", "application/json");
+  this.symbolRequest.setRequestHeader("Content-length",
+                                      requestJSON.length);
+  this.symbolRequest.setRequestHeader("Connection", "close");
+  this.symbolRequest.onreadystatechange = this.handleSymbolResponse.bind(this);
+  this.symbolRequest.send(requestJSON);
+}
+
 let ChromeHangs = {
 
   symbolRequest: null,
 
   /**
    * Renders raw chrome hang data
    */
   render: function ChromeHangs_render() {
@@ -355,49 +382,16 @@ let ChromeHangs = {
 
     let durations = Telemetry.chromeHangs.durations;
     let titleText = bundle.formatStringFromName(
       "hangTitle", [aIndex + 1, durations[aIndex]], 2);
     titleElement.appendChild(document.createTextNode(titleText));
 
     div.appendChild(titleElement);
     div.appendChild(document.createElement("br"));
-  },
-
-  /**
-   * Sends a symbolication request for the recorded hangs
-   */
-  fetchSymbols: function ChromeHangs_fetchSymbols() {
-    let symbolServerURI =
-      getPref(PREF_SYMBOL_SERVER_URI, DEFAULT_SYMBOL_SERVER_URI);
-
-    let hangs = Telemetry.chromeHangs;
-    let memoryMap = hangs.memoryMap;
-    let stacks = hangs.stacks;
-    let request = {"memoryMap" : memoryMap, "stacks" : stacks,
-                   "version" : 3};
-    let requestJSON = JSON.stringify(request);
-
-    this.symbolRequest = XMLHttpRequest();
-    this.symbolRequest.open("POST", symbolServerURI, true);
-    this.symbolRequest.setRequestHeader("Content-type", "application/json");
-    this.symbolRequest.setRequestHeader("Content-length", requestJSON.length);
-    this.symbolRequest.setRequestHeader("Connection", "close");
-
-    this.symbolRequest.onreadystatechange = this.handleSymbolResponse.bind(this);
-    this.symbolRequest.send(requestJSON);
-  },
-
-  /**
-   * Called when the 'readyState' of the XMLHttpRequest changes. We only care
-   * about state 4 ("completed") - handling the response data.
-   */
-  handleSymbolResponse: function ChromeHangs_handleSymbolResponse() {
-    StackRenderer.renderSymbolicatedStacks("chrome-hangs", this.symbolRequest,
-                                           this.renderHangHeader);
   }
 };
 
 let Histogram = {
 
   hgramSamplesCaption: bundle.GetStringFromName("histogramSamples"),
 
   hgramAverageCaption: bundle.GetStringFromName("histogramAverage"),
@@ -657,24 +651,44 @@ function setupListeners() {
   document.getElementById("toggle-telemetry").addEventListener("click",
     function () {
       let value = getPref(PREF_TELEMETRY_ENABLED, false);
       Services.prefs.setBoolPref(PREF_TELEMETRY_ENABLED, !value);
   }, false);
 
   document.getElementById("chrome-hangs-fetch-symbols").addEventListener("click",
     function () {
-      ChromeHangs.fetchSymbols();
+      let hangs = Telemetry.chromeHangs;
+      let req = new SymbolicationRequest("chrome-hangs",
+                                         ChromeHangs.renderHangHeader,
+                                         hangs.memoryMap, hangs.stacks);
+      req.fetchSymbols();
   }, false);
 
   document.getElementById("chrome-hangs-hide-symbols").addEventListener("click",
     function () {
       ChromeHangs.render();
   }, false);
 
+  document.getElementById("late-writes-fetch-symbols").addEventListener("click",
+    function () {
+      let lateWrites = TelemetryPing.getPayload().lateWrites;
+      let req = new SymbolicationRequest("late-writes", function() {},
+                                         lateWrites.memoryMap,
+                                         lateWrites.stacks);
+      req.fetchSymbols();
+  }, false);
+
+  document.getElementById("late-writes-hide-symbols").addEventListener("click",
+    function () {
+      let ping = TelemetryPing.getPayload();
+      LateWritesSingleton.renderLateWrites(ping.lateWrites);
+  }, false);
+
+
   // Clicking on the section name will toggle its state
   let sectionHeaders = document.getElementsByClassName("section-name");
   for (let sectionHeader of sectionHeaders) {
     sectionHeader.addEventListener("click", toggleSection, false);
   }
 
   // Clicking on the "collapse"/"expand" text will also toggle section's state
   let toggleLinks = document.getElementsByClassName("toggle-caption");

--- a/toolkit/content/aboutTelemetry.xhtml
+++ b/toolkit/content/aboutTelemetry.xhtml
@@ -82,17 +82,18 @@
     </section>
 
     <section id="late-writes-section" class="data-section">
       <h1 class="section-name">&aboutTelemetry.lateWritesSection;</h1>
       <span class="toggle-caption">&aboutTelemetry.toggleOn;</span>
       <span class="toggle-caption hidden">&aboutTelemetry.toggleOff;</span>
       <span class="empty-caption hidden">&aboutTelemetry.emptySection;</span>
       <div id="late-writes" class="data hidden">
-        <!-- FIXME: add fetch-symbols and hide-symbols -->
+        <a id="late-writes-fetch-symbols" href="javascript:">&aboutTelemetry.fetchSymbols;</a>
+        <a id="late-writes-hide-symbols" class="hidden" href="javascript:">&aboutTelemetry.hideSymbols;</a>
         <br/>
         <br/>
         <div id="late-writes-data">
         </div>
       </div>
     </section>
 
     <section id="system-info-section" class="data-section">