--- a/devtools/client/netmonitor/components/request-list-empty.js
+++ b/devtools/client/netmonitor/components/request-list-empty.js
@@ -28,38 +28,35 @@ const RequestListEmptyNotice = createCla
   propTypes: {
     onReloadClick: PropTypes.func.isRequired,
     onPerfClick: PropTypes.func.isRequired,
   },
 
   render() {
     return div(
       {
-        id: "requests-list-empty-notice",
-        className: "request-list-empty-notice",
+        className: "requests-list-empty-notice",
       },
-      div({ id: "notice-reload-message" },
+      div({ className: "notice-reload-message" },
         span(null, L10N.getStr("netmonitor.reloadNotice1")),
         button(
           {
-            id: "requests-list-reload-notice-button",
-            className: "devtools-toolbarbutton",
+            className: "devtools-toolbarbutton requests-list-reload-notice-button",
             "data-standalone": true,
             onClick: this.props.onReloadClick,
           },
           L10N.getStr("netmonitor.reloadNotice2")
         ),
         span(null, L10N.getStr("netmonitor.reloadNotice3"))
       ),
-      div({ id: "notice-perf-message" },
+      div({ className: "notice-perf-message" },
         span(null, L10N.getStr("netmonitor.perfNotice1")),
         button({
-          id: "requests-list-perf-notice-button",
           title: L10N.getStr("netmonitor.perfNotice3"),
-          className: "devtools-button",
+          className: "devtools-button requests-list-perf-notice-button",
           "data-standalone": true,
           onClick: this.props.onPerfClick,
         }),
         span(null, L10N.getStr("netmonitor.perfNotice2"))
       )
     );
   }
 });

--- a/devtools/client/netmonitor/components/request-list-header.js
+++ b/devtools/client/netmonitor/components/request-list-header.js
@@ -74,17 +74,17 @@ const RequestListHeader = createClass({
     this.background = null;
   },
 
   render() {
     const { sort, scale, waterfallWidth, onHeaderClick } = this.props;
 
     return div(
       { className: "devtools-toolbar requests-list-toolbar" },
-      div({ id: "toolbar-labels" },
+      div({ className: "toolbar-labels" },
         HEADERS.map(header => {
           const name = header.name;
           const boxName = header.boxName || name;
           const label = L10N.getStr(`netmonitor.toolbar.${header.label || name}`);
 
           let sorted, sortedTitle;
           const active = sort.type == name ? true : undefined;
           if (active) {

--- a/devtools/client/netmonitor/test/browser_net_reload-button.js
+++ b/devtools/client/netmonitor/test/browser_net_reload-button.js
@@ -10,16 +10,16 @@
 add_task(function* () {
   let { monitor } = yield initNetMonitor(SIMPLE_URL);
   info("Starting test... ");
 
   let { document } = monitor.panelWin;
 
   let wait = waitForNetworkEvents(monitor, 1);
   EventUtils.sendMouseEvent({ type: "click" },
-    document.querySelector("#requests-list-reload-notice-button"));
+    document.querySelector(".requests-list-reload-notice-button"));
   yield wait;
 
   is(document.querySelectorAll(".request-list-item").length, 1,
     "The request list should have one item after reloading");
 
   return teardown(monitor);
 });

--- a/devtools/client/netmonitor/test/browser_net_reload-markers.js
+++ b/devtools/client/netmonitor/test/browser_net_reload-markers.js
@@ -8,17 +8,17 @@
  */
 
 add_task(function* () {
   let { monitor } = yield initNetMonitor(SIMPLE_URL);
   info("Starting test... ");
 
   let { document, windowRequire } = monitor.panelWin;
   let { EVENTS } = windowRequire("devtools/client/netmonitor/events");
-  let button = document.querySelector("#requests-list-reload-notice-button");
+  let button = document.querySelector(".requests-list-reload-notice-button");
   button.click();
 
   let markers = [];
 
   monitor.panelWin.on(EVENTS.TIMELINE_EVENT, (_, marker) => {
     markers.push(marker);
   });
 

--- a/devtools/client/themes/netmonitor.css
+++ b/devtools/client/themes/netmonitor.css
@@ -5,17 +5,17 @@
 @import "resource://devtools/client/shared/components/tree/tree-view.css";
 @import "resource://devtools/client/shared/components/tabs/tabs.css";
 @import "resource://devtools/client/shared/components/tabs/tabbar.css";
 
 * {
   box-sizing: border-box;
 }
 
-#toolbar-labels {
+.toolbar-labels {
   overflow: hidden;
   display: flex;
   flex: auto;
 }
 
 .devtools-toolbar-container {
   display: flex;
   justify-content: space-between;
@@ -88,32 +88,32 @@
 }
 
 .request-list-empty-notice {
   margin: 0;
   padding: 12px;
   font-size: 120%;
 }
 
-#notice-perf-message {
+.notice-perf-message {
   margin-top: 2px;
 }
 
-#requests-list-perf-notice-button {
+.requests-list-perf-notice-button {
   min-width: 30px;
   min-height: 26px;
   margin: 0 5px;
   vertical-align: middle;
 }
 
-#requests-list-perf-notice-button::before {
+.requests-list-perf-notice-button::before {
   background-image: url(images/profiler-stopwatch.svg);
 }
 
-#requests-list-reload-notice-button {
+.requests-list-reload-notice-button {
   font-size: inherit;
   min-height: 26px;
   padding-left: 10px;
   padding-right: 10px;
   margin: 0 5px;
   background-color: var(--theme-toolbar-background);
 }