3 files changed, 17 insertions, 18 deletions
diff --git a/ext/js/application.js b/ext/js/application.js
index 227e9d5e..d7ab6725 100644
--- a/ext/js/application.js
+++ b/ext/js/application.js
@@ -76,14 +76,6 @@ export class Application extends EventDispatcher {
             // NOP
         }
 
-        /** @type {?string} */
-        this._extensionUrlBase = null;
-        try {
-            this._extensionUrlBase = this._webExtension.getUrl('/');
-        } catch (e) {
-            // NOP
-        }
-
         /** @type {?boolean} */
         this._isBackground = null;
         /** @type {API} */
@@ -148,15 +140,6 @@ export class Application extends EventDispatcher {
         this._webExtension.sendMessagePromise({action: 'applicationReady'});
     }
 
-    /**
-     * Checks whether or not a URL is an extension URL.
-     * @param {string} url The URL to check.
-     * @returns {boolean} `true` if the URL is an extension URL, `false` otherwise.
-     */
-    isExtensionUrl(url) {
-        return this._extensionUrlBase !== null && url.startsWith(this._extensionUrlBase);
-    }
-
     /** */
     triggerStorageChanged() {
         this.trigger('storageChanged', {});
diff --git a/ext/js/dom/style-util.js b/ext/js/dom/style-util.js
index e5046e5c..c2c620f6 100644
--- a/ext/js/dom/style-util.js
+++ b/ext/js/dom/style-util.js
@@ -62,7 +62,7 @@ function setInjectedStylesheet(id, parentNode, value) {
  * @throws {Error}
  */
 export async function loadStyle(application, id, type, value, useWebExtensionApi = false, parentNode = null) {
-    if (useWebExtensionApi && application.isExtensionUrl(window.location.href)) {
+    if (useWebExtensionApi && application.webExtension.isExtensionUrl(window.location.href)) {
         // Permissions error will occur if trying to use the WebExtension API to inject into an extension page
         useWebExtensionApi = false;
     }
diff --git a/ext/js/extension/web-extension.js b/ext/js/extension/web-extension.js
index 2aafbe92..bdc9b1b3 100644
--- a/ext/js/extension/web-extension.js
+++ b/ext/js/extension/web-extension.js
@@ -26,6 +26,13 @@ export class WebExtension extends EventDispatcher {
         super();
         /** @type {boolean} */
         this._unloaded = false;
+        /** @type {?string} */
+        this._extensionBaseUrl = null;
+        try {
+            this._extensionBaseUrl = this.getUrl('/');
+        } catch (e) {
+            // NOP
+        }
     }
 
     /** @type {boolean} */
@@ -105,4 +112,13 @@ export class WebExtension extends EventDispatcher {
         this._unloaded = true;
         this.trigger('unloaded', {});
     }
+
+    /**
+     * Checks whether or not a URL is an extension URL.
+     * @param {string} url The URL to check.
+     * @returns {boolean} `true` if the URL is an extension URL, `false` otherwise.
+     */
+    isExtensionUrl(url) {
+        return this._extensionBaseUrl !== null && url.startsWith(this._extensionBaseUrl);
+    }
 }