--- a/devtools/client/netmonitor/initializer.js
+++ b/devtools/client/netmonitor/initializer.js
@@ -100,54 +100,39 @@ window.Netmonitor = {
 
   // Support for WebExtensions API
 
   /**
    * Support for `devtools.network.getHAR` (get collected data as HAR)
    */
   getHar() {
     let { HarExporter } = require("devtools/client/netmonitor/src/har/har-exporter");
-    let {
-      getLongString,
-      getTabTarget,
-      getTimingMarker,
-      requestData,
-    } = connector;
-    let { form: { title, url } } = getTabTarget();
     let state = store.getState();
 
     let options = {
-      getString: getLongString,
+      connector,
       items: getSortedRequests(state),
-      requestData,
-      getTimingMarker,
-      title: title || url,
     };
 
     return HarExporter.getHar(options);
   },
 
   /**
    * Support for `devtools.network.onRequestFinished`. A hook for
    * every finished HTTP request used by WebExtensions API.
    */
   onRequestAdded(event, requestId) {
     let listeners = this.toolbox.getRequestFinishedListeners();
     if (!listeners.size) {
       return;
     }
 
     let { HarExporter } = require("devtools/client/netmonitor/src/har/har-exporter");
-    let { getLongString, getTabTarget, requestData } = connector;
-    let { form: { title, url } } = getTabTarget();
-
     let options = {
-      getString: getLongString,
-      requestData,
-      title: title || url,
+      connector,
       includeResponseBodies: false,
       items: [getDisplayedRequestById(store.getState(), requestId)],
     };
 
     // Build HAR for specified request only.
     HarExporter.getHar(options).then(har => {
       let harEntry = har.log.entries[0];
       delete harEntry.pageref;

--- a/devtools/client/netmonitor/src/har/har-exporter.js
+++ b/devtools/client/netmonitor/src/har/har-exporter.js
@@ -181,20 +181,38 @@ const HarExporter = {
   },
 
   /**
    * Build HAR data object. This object contains all HTTP data
    * collected by the Network panel. The process is asynchronous
    * since it can involve additional RDP communication (e.g. resolving
    * long strings).
    */
-  buildHarData: function (options) {
+  buildHarData: async function (options) {
+    let { connector } = options;
+    let {
+      getTabTarget,
+    } = connector;
+    let {
+      form: { title, url }
+    } = getTabTarget();
+
+    options = {
+      ...options,
+      title: title || url,
+      getString: connector.getLongString,
+      getTimingMarker: connector.getTimingMarker,
+      requestData: connector.requestData,
+    };
+
     // Build HAR object from collected data.
     let builder = new HarBuilder(options);
-    return builder.build();
+    let result = await builder.build();
+
+    return result;
   },
 
   /**
    * Build JSON string from the HAR data object.
    */
   stringify: function (har) {
     if (!har) {
       return null;

--- a/devtools/client/netmonitor/src/widgets/RequestListContextMenu.js
+++ b/devtools/client/netmonitor/src/widgets/RequestListContextMenu.js
@@ -404,27 +404,16 @@ class RequestListContextMenu {
     // This will not work in launchpad
     // document.execCommand(‘cut’/‘copy’) was denied because it was not called from
     // inside a short running user-generated event handler.
     // https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Interact_with_the_clipboard
     return HarExporter.save(this.getDefaultHarOptions(sortedRequests));
   }
 
   getDefaultHarOptions(sortedRequests) {
-    let {
-      getLongString,
-      getTabTarget,
-      requestData,
-      getTimingMarker,
-    } = this.props.connector;
-    let { form: { title, url } } = getTabTarget();
-
     return {
-      getString: getLongString,
+      connector: this.props.connector,
       items: sortedRequests,
-      requestData,
-      getTimingMarker,
-      title: title || url,
     };
   }
 }
 
 module.exports = RequestListContextMenu;