more headless patches to address pipeline clog; 'two-browsers' may not have been doing anything before

src/functional_tests/base.py

@@ -38,17 +38,10 @@ def wait(fn):
 class FunctionalTest(StaticLiveServerTestCase):
     # Helper methods
     def _make_browser(self, width=1366, height=900):
-        """Create a Firefox instance sized to width×height.
-        In headless CI, pass --width/--height as binary args so the CSS
-        media query (orientation: landscape/portrait) is correct from the
-        first paint — set_window_size() alone is unreliable in headless mode.
-        """
+        """Create a Firefox instance sized to width×height."""
         options = webdriver.FirefoxOptions()
-        headless = os.environ.get("HEADLESS")
-        if headless:
+        if os.environ.get("HEADLESS"):
             options.add_argument("--headless")
-            options.add_argument(f"--width={width}")
-            options.add_argument(f"--height={height}")
         browser = webdriver.Firefox(options=options)
         browser.set_window_size(width, height)
         return browser