diff --git a/testing/mozbase/mozdevice/mozdevice/adb.py b/testing/mozbase/mozdevice/mozdevice/adb.py
index fefc8c532f7f..25142caf9f44 100644
--- a/testing/mozbase/mozdevice/mozdevice/adb.py
+++ b/testing/mozbase/mozdevice/mozdevice/adb.py
@@ -2990,13 +2990,21 @@ class ADBDevice(ADBCommand):
         :raises: * ADBTimeoutError
                  * ADBError
         """
+        if self.version < version_codes.Q:
+            return self._get_top_activity_P(timeout=timeout)
+        return self._get_top_activity_Q(timeout=timeout)
+
+    def _get_top_activity_P(self, timeout=None):
+        """Returns the name of the top activity (focused app) reported by dumpsys
+        for Android 9 and earlier.
+        """
         package = None
         data = None
         cmd = "dumpsys window windows"
         try:
             data = self.shell_output(cmd, timeout=timeout)
         except Exception:
-            # dumpsys intermittently fails on some platforms (4.3 arm emulator)
+            # dumpsys intermittently fails on some platforms.
             return package
         m = re.search('mFocusedApp(.+)/', data)
         if not m:
@@ -3012,6 +3020,30 @@ class ADBDevice(ADBCommand):
             self._logger.debug('get_top_activity: %s' % str(package))
         return package
 
+    def _get_top_activity_Q(self, timeout=None):
+        """Returns the name of the top activity (focused app) reported by dumpsys
+        for Android 10 and later.
+        """
+        package = None
+        data = None
+        cmd = "dumpsys window"
+        try:
+            data = self.shell_output(cmd, timeout=timeout)
+        except Exception:
+            # dumpsys intermittently fails on some platforms (4.3 arm emulator)
+            return package
+        m = re.search('mFocusedApp=AppWindowToken{\w+ token=Token{'
+                      '\w+ ActivityRecord{\w+ w+ (\w+)/w+ \w+}}}', data)
+        if m:
+            line = m.group(1)
+            # Extract package name: string of non-whitespace ending in forward slash
+            m = re.search('(\S+)/', line)
+            if m:
+                package = m.group(1)
+        if self._verbose:
+            self._logger.debug('get_top_activity: %s' % str(package))
+        return package
+
     # System control methods
 
     def is_device_ready(self, timeout=None):
diff --git a/testing/mozbase/mozdevice/mozdevice/version_codes.py b/testing/mozbase/mozdevice/mozdevice/version_codes.py
index 369a294ad5e2..15ef59b2159c 100644
--- a/testing/mozbase/mozdevice/mozdevice/version_codes.py
+++ b/testing/mozbase/mozdevice/mozdevice/version_codes.py
@@ -66,3 +66,5 @@ O = 26
 O_MR1 = 27
 # Pie
 P = 28
+# 10
+Q = 29