diff --git a/core/constants.js b/core/constants.js
index 27698f90..bd4550ec 100644
--- a/core/constants.js
+++ b/core/constants.js
@@ -214,7 +214,7 @@ const Links = {
     'FAQ_HTML_FILTER': chrome.extension.getURL('pages/help/help.html#html-filter'),
     'STATISTICS': chrome.extension.getURL('pages/statistics/statistics.html'),
     'LOCALCDN_TEST': 'https://www.localcdn.org/test',
-    'LOCALCDN_TEST_WEBSITE': 'https://www.localcdn.org/test/check?domain=',
+    'LOCALCDN_TEST_WEBSITE': 'https://www.localcdn.org/test/check',
     'WEBLATE': 'https://hosted.weblate.org/projects/localcdn/localcdn/',
 };
 
diff --git a/core/messenger.js b/core/messenger.js
index fd2c16e6..394bf106 100644
--- a/core/messenger.js
+++ b/core/messenger.js
@@ -97,6 +97,16 @@ messenger._handleMessageReceived = function (message, sender, sendResponse) {
     if (topic === 'deleteStatistic') {
         storageManager.statistics = {};
     }
+
+    if (topic === 'injection') {
+
+        chrome.tabs.executeScript(value, {
+            'code': `window.addEventListener('load', () => {
+                document.getElementById('domain').value = '${message.url}';
+            });`,
+            'runAt': 'document_start'
+        });
+    }
 };
 
 
diff --git a/pages/popup/popup.js b/pages/popup/popup.js
index 594ef56f..07a21b8f 100644
--- a/pages/popup/popup.js
+++ b/pages/popup/popup.js
@@ -439,8 +439,10 @@ popup._onDocumentLoaded = function () {
 popup._onTestingUtilityLinkClicked = function (event) {
     if (event.button === 0 || event.button === 1) {
         chrome.tabs.create({
-            'url': Links.LOCALCDN_TEST_WEBSITE + popup._targetTab.url,
+            'url': Links.LOCALCDN_TEST_WEBSITE,
             'active': event.button === 0,
+        }, function (tab) {
+            popup._injectDomain(tab.id);
         });
     }
 
@@ -449,6 +451,16 @@ popup._onTestingUtilityLinkClicked = function (event) {
     }
 };
 
+popup._injectDomain = function (tabId) {
+    let message = {
+        'topic': 'injection',
+        'value': tabId,
+        'url': popup._targetTab.url
+    };
+
+    chrome.runtime.sendMessage(message);
+};
+
 popup._onOptionsButtonClicked = function () {
     chrome.runtime.openOptionsPage();
     return window.close();