1 files changed, 30 insertions, 0 deletions
diff --git a/browser/base/content/test/pageStyle/head.js b/browser/base/content/test/pageStyle/head.js
new file mode 100644
index 0000000000..57d5947d50
--- /dev/null
+++ b/browser/base/content/test/pageStyle/head.js
@@ -0,0 +1,30 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const WEB_ROOT = getRootDirectory(gTestPath).replace(
+  "chrome://mochitests/content",
+  "https://example.com"
+);
+
+/**
+ * Waits for the stylesheets to be loaded into the browser menu.
+ *
+ * @param browser
+ *        The browser that contains the webpage we're testing.
+ * @param styleSheetCount
+ *        How many stylesheets we expect to be loaded.
+ * @return Promise
+ */
+function promiseStylesheetsLoaded(browser, styleSheetCount) {
+  return TestUtils.waitForCondition(() => {
+    let actor =
+      browser.browsingContext?.currentWindowGlobal?.getActor("PageStyle");
+    if (!actor) {
+      info("No jswindowactor (yet?)");
+      return false;
+    }
+    let sheetCount = actor.getSheetInfo().filteredStyleSheets.length;
+    info(`waiting for sheets: ${sheetCount}`);
+    return sheetCount >= styleSheetCount;
+  }, "waiting for style sheets to load");
+}