--- a/devtools/client/netmonitor/src/components/RequestListColumnCause.js
+++ b/devtools/client/netmonitor/src/components/RequestListColumnCause.js
@@ -11,44 +11,34 @@ const {
 } = require("devtools/client/shared/vendor/react");
 
 const { div } = DOM;
 
 class RequestListColumnCause extends Component {
   static get propTypes() {
     return {
       item: PropTypes.object.isRequired,
-      onCauseBadgeMouseDown: PropTypes.func.isRequired,
     };
   }
 
   shouldComponentUpdate(nextProps) {
     return this.props.item.cause !== nextProps.item.cause;
   }
 
   render() {
-    let {
-      item: { cause },
-      onCauseBadgeMouseDown,
-    } = this.props;
+    let { item: { cause } } = this.props;
 
-    let causeType = "unknown";
-    let causeHasStack = false;
+    let causeType = "--";
 
     if (cause) {
-      // Legacy server might send a numeric value. Display it as "unknown"
-      causeType = typeof cause.type === "string" ? cause.type : "unknown";
-      causeHasStack = cause.stacktrace && cause.stacktrace.length > 0;
+      // Legacy server might send a numeric value. Display it as "--"
+      causeType = typeof cause.type === "string" ? cause.type : "--";
     }
 
     return (
       div({ className: "requests-list-column requests-list-cause", title: causeType },
-        causeHasStack && div({
-          className: "requests-list-cause-stack",
-          onMouseDown: onCauseBadgeMouseDown,
-        }, "JS"),
         causeType
       )
     );
   }
 }
 
 module.exports = RequestListColumnCause;

--- a/devtools/client/netmonitor/src/components/RequestListContent.js
+++ b/devtools/client/netmonitor/src/components/RequestListContent.js
@@ -38,17 +38,16 @@ class RequestListContent extends Compone
   static get propTypes() {
     return {
       connector: PropTypes.object.isRequired,
       columns: PropTypes.object.isRequired,
       dispatch: PropTypes.func.isRequired,
       displayedRequests: PropTypes.object.isRequired,
       firstRequestStartedMillis: PropTypes.number.isRequired,
       fromCache: PropTypes.bool,
-      onCauseBadgeMouseDown: PropTypes.func.isRequired,
       onItemMouseDown: PropTypes.func.isRequired,
       onSelectDelta: PropTypes.func.isRequired,
       onWaterfallMouseDown: PropTypes.func.isRequired,
       scale: PropTypes.number,
       selectedRequestId: PropTypes.string,
     };
   }
 
@@ -212,17 +211,16 @@ class RequestListContent extends Compone
     this.shouldScrollBottom = false;
   }
 
   render() {
     const {
       columns,
       displayedRequests,
       firstRequestStartedMillis,
-      onCauseBadgeMouseDown,
       onItemMouseDown,
       onWaterfallMouseDown,
       scale,
       selectedRequestId,
     } = this.props;
 
     return (
       div({ className: "requests-list-wrapper"},
@@ -241,17 +239,16 @@ class RequestListContent extends Compone
               columns,
               item,
               index,
               isSelected: item.id === selectedRequestId,
               key: item.id,
               onContextMenu: this.onContextMenu,
               onFocusedNodeChange: this.onFocusedNodeChange,
               onMouseDown: () => onItemMouseDown(item.id),
-              onCauseBadgeMouseDown: () => onCauseBadgeMouseDown(item.cause),
               onWaterfallMouseDown: () => onWaterfallMouseDown(),
             }))
           )
         )
       )
     );
   }
 }
@@ -261,24 +258,16 @@ module.exports = connect(
     columns: state.ui.columns,
     displayedRequests: getDisplayedRequests(state),
     firstRequestStartedMillis: state.requests.firstStartedMillis,
     selectedRequestId: state.requests.selectedId,
     scale: getWaterfallScale(state),
   }),
   (dispatch) => ({
     dispatch,
-    /**
-     * A handler that opens the stack trace tab when a stack trace is available
-     */
-    onCauseBadgeMouseDown: (cause) => {
-      if (cause.stacktrace && cause.stacktrace.length > 0) {
-        dispatch(Actions.selectDetailsPanelTab("stack-trace"));
-      }
-    },
     onItemMouseDown: (id) => dispatch(Actions.selectRequest(id)),
     onSelectDelta: (delta) => dispatch(Actions.selectDelta(delta)),
     /**
      * A handler that opens the timing sidebar panel if the waterfall is clicked.
      */
     onWaterfallMouseDown: () => {
       dispatch(Actions.selectDetailsPanelTab("timings"));
     },

--- a/devtools/client/netmonitor/src/components/RequestListItem.js
+++ b/devtools/client/netmonitor/src/components/RequestListItem.js
@@ -76,17 +76,16 @@ class RequestListItem extends Component 
   static get propTypes() {
     return {
       columns: PropTypes.object.isRequired,
       item: PropTypes.object.isRequired,
       index: PropTypes.number.isRequired,
       isSelected: PropTypes.bool.isRequired,
       firstRequestStartedMillis: PropTypes.number.isRequired,
       fromCache: PropTypes.bool,
-      onCauseBadgeMouseDown: PropTypes.func.isRequired,
       onContextMenu: PropTypes.func.isRequired,
       onFocusedNodeChange: PropTypes.func,
       onMouseDown: PropTypes.func.isRequired,
       onWaterfallMouseDown: PropTypes.func.isRequired,
       waterfallWidth: PropTypes.number,
     };
   }
 
@@ -116,17 +115,16 @@ class RequestListItem extends Component 
       columns,
       item,
       index,
       isSelected,
       firstRequestStartedMillis,
       fromCache,
       onContextMenu,
       onMouseDown,
-      onCauseBadgeMouseDown,
       onWaterfallMouseDown,
     } = this.props;
 
     let classList = ["request-list-item", index % 2 ? "odd" : "even"];
     isSelected && classList.push("selected");
     fromCache && classList.push("fromCache");
 
     return (
@@ -140,17 +138,17 @@ class RequestListItem extends Component 
       },
         columns.get("status") && RequestListColumnStatus({ item }),
         columns.get("method") && RequestListColumnMethod({ item }),
         columns.get("file") && RequestListColumnFile({ item }),
         columns.get("protocol") && RequestListColumnProtocol({ item }),
         columns.get("scheme") && RequestListColumnScheme({ item }),
         columns.get("domain") && RequestListColumnDomain({ item }),
         columns.get("remoteip") && RequestListColumnRemoteIP({ item }),
-        columns.get("cause") && RequestListColumnCause({ item, onCauseBadgeMouseDown }),
+        columns.get("cause") && RequestListColumnCause({ item }),
         columns.get("type") && RequestListColumnType({ item }),
         columns.get("cookies") && RequestListColumnCookies({ item }),
         columns.get("setCookies") && RequestListColumnSetCookies({ item }),
         columns.get("transferred") && RequestListColumnTransferredSize({ item }),
         columns.get("contentSize") && RequestListColumnContentSize({ item }),
         columns.get("startTime") &&
           RequestListColumnStartTime({ item, firstRequestStartedMillis }),
         columns.get("endTime") &&