diff --git a/browser/devtools/netmonitor/netmonitor.css b/browser/devtools/netmonitor/netmonitor.css
index a031d6446a1..e7652db75ec 100644
--- a/browser/devtools/netmonitor/netmonitor.css
+++ b/browser/devtools/netmonitor/netmonitor.css
@@ -28,6 +28,11 @@
   overflow: auto;
 }
 
+#headers-summary-url-value .textbox-input {
+  /* workaround for textbox not supporting the @crop attribute */
+  text-overflow: ellipsis;
+}
+
 /* Responsive sidebar */
 @media (max-width: 700px) {
   #toolbar-spacer,
diff --git a/browser/devtools/netmonitor/netmonitor.xul b/browser/devtools/netmonitor/netmonitor.xul
index 1aafcd8b826..c31d6026847 100644
--- a/browser/devtools/netmonitor/netmonitor.xul
+++ b/browser/devtools/netmonitor/netmonitor.xul
@@ -299,10 +299,10 @@
                         align="center">
                     <label class="plain tabpanel-summary-label"
                            value="&netmonitorUI.summary.url;"/>
-                    <label id="headers-summary-url-value"
-                           class="plain tabpanel-summary-value devtools-monospace"
-                           crop="end"
-                           flex="1"/>
+                    <textbox id="headers-summary-url-value"
+                             class="plain tabpanel-summary-value devtools-monospace"
+                             flex="1"
+                             readonly="true"/>
                   </hbox>
                   <hbox id="headers-summary-method"
                         class="tabpanel-summary-container"