--- a/testing/mozharness/mozharness/mozilla/testing/testbase.py
+++ b/testing/mozharness/mozharness/mozilla/testing/testbase.py
@@ -680,17 +680,24 @@ Did you run with --create-virtualenv? Is
 
         self.info('Minidump tooltool manifest unknown. Determining based upon '
                   'platform and architecture.')
         platform_name = self.platform_name()
 
         if platform_name:
             tooltool_path = "config/tooltool-manifests/%s/releng.manifest" % \
                 TOOLTOOL_PLATFORM_DIR[platform_name]
-            return tooltool_path
+
+            # If we're running from a source checkout, reference the manifest
+            # from there. Otherwise, assume the path is relative to pwd and
+            # comes from common.tests.zip.
+            if self.topsrcdir:
+                return os.path.join(self.topsrcdir, 'testing', tooltool_path)
+            else:
+                return tooltool_path
         else:
             self.fatal('We could not determine the minidump\'s filename.')
 
     def query_minidump_filename(self):
         if self.config.get('minidump_stackwalk_path'):
             return self.config['minidump_stackwalk_path']
 
         self.info('Minidump filename unknown. Determining based upon platform '

--- a/testing/mozharness/scripts/web_platform_tests.py
+++ b/testing/mozharness/scripts/web_platform_tests.py
@@ -178,17 +178,16 @@ class WebPlatformTest(TestingMixin, Merc
         cmd.extend(self.query_tests_args(try_tests,
                                          str_format_values=str_format_values))
 
         return cmd
 
     def download_and_extract(self):
         super(WebPlatformTest, self).download_and_extract(
             extract_dirs=["bin/*",
-                          "config/*",
                           "mozinfo.json"],
             suite_categories=["web-platform"])
 
     def run_tests(self):
         dirs = self.query_abs_dirs()
         cmd = self._query_cmd()
 
         parser = StructuredOutputParser(config=self.config,