--- a/devtools/qunit.py	Thu Sep 25 17:38:51 2014 +0200
+++ b/devtools/qunit.py	Fri Aug 01 19:28:44 2014 +0200
@@ -62,34 +62,18 @@
 
     def __init__(self, url=None):
         self._process = None
-        self._tmp_dir = mkdtemp(prefix='cwtest-ffxprof-')
-        self._profile_data = {'uid': uuid4()}
-        self._profile_name = self.profile_name_mask % self._profile_data
-        stdout = TemporaryFile()
-        stderr = TemporaryFile()
+        self._profile_dir = mkdtemp(prefix='cwtest-ffxprof-')
         self.firefox_cmd = ['firefox', '-no-remote']
         if os.name == 'posix':
             self.firefox_cmd = [osp.join(osp.dirname(__file__), 'data', 'xvfb-run.sh'),
                                 '-a', '-s', '-noreset -screen 0 640x480x8'] + self.firefox_cmd
-        try:
-            home = osp.expanduser('~')
-            user = getlogin()
-            assert os.access(home, os.W_OK), \
-                   'No write access to your home directory, Firefox will crash.'\
-                   ' Are you sure "%s" is a valid home  for user "%s"' % (home, user)
-            check_call(self.firefox_cmd + ['-CreateProfile',
-                        '%s %s' % (self._profile_name, self._tmp_dir)],
-                                   stdout=stdout, stderr=stderr)
-        except CalledProcessError as cpe:
-            stdout.seek(0)
-            stderr.seek(0)
-            raise VerboseCalledProcessError(cpe.returncode, cpe.cmd, stdout.read(), stderr.read())
 
     def start(self, url):
         self.stop()
-        fnull = open(os.devnull, 'w')
-        self._process = Popen(self.firefox_cmd + ['-P', self._profile_name, url],
-                              stdout=fnull, stderr=fnull)
+        cmd = self.firefox_cmd + ['-silent', '--profile', self._profile_dir,
+                                  '-url', url]
+        with open(os.devnull, 'w') as fnull:
+            self._process = Popen(cmd, stdout=fnull, stderr=fnull)
 
     def stop(self):
         if self._process is not None:
@@ -100,7 +84,7 @@
 
     def __del__(self):
         self.stop()
-        rmtree(self._tmp_dir)
+        rmtree(self._profile_dir)
 
 
 class QUnitTestCase(CubicWebServerTC):
@@ -169,6 +153,12 @@
             self.test_queue.get(False)
 
         browser = FirefoxHelper()
+        # start firefox once to let it init the profile (and run system-wide
+        # add-ons post setup, blegh), and then kill it ...
+        browser.start('about:blank')
+        import time; time.sleep(5)
+        browser.stop()
+        # ... then actually run the test file
         browser.start(html_test_file.name)
         test_count = 0
         error = False