diff --git a/homeassistant/components/airvisual/__init__.py b/homeassistant/components/airvisual/__init__.py
index e5d8b03f316..96b3770974a 100644
--- a/homeassistant/components/airvisual/__init__.py
+++ b/homeassistant/components/airvisual/__init__.py
@@ -38,7 +38,7 @@ from .const import (
 PLATFORMS = ["air_quality", "sensor"]
 
 DEFAULT_ATTRIBUTION = "Data provided by AirVisual"
-DEFAULT_NODE_PRO_SCAN_INTERVAL = timedelta(minutes=1)
+DEFAULT_NODE_PRO_UPDATE_INTERVAL = timedelta(minutes=1)
 DEFAULT_OPTIONS = {CONF_SHOW_ON_MAP: True}
 
 GEOGRAPHY_COORDINATES_SCHEMA = vol.Schema(
@@ -95,27 +95,43 @@ def async_get_cloud_api_update_interval(hass, api_key):
     This will shift based on the number of active consumers, thus keeping the user
     under the monthly API limit.
     """
-    num_consumers = len(
-        {
-            config_entry
-            for config_entry in hass.config_entries.async_entries(DOMAIN)
-            if config_entry.data.get(CONF_API_KEY) == api_key
-        }
-    )
+    num_consumers = len(async_get_cloud_coordinators_by_api_key(hass, api_key))
 
     # Assuming 10,000 calls per month and a "smallest possible month" of 28 days; note
     # that we give a buffer of 1500 API calls for any drift, restarts, etc.:
     minutes_between_api_calls = ceil(1 / (8500 / 28 / 24 / 60 / num_consumers))
+
+    LOGGER.debug(
+        "Leveling API key usage (%s): %s consumers, %s minutes between updates",
+        api_key,
+        num_consumers,
+        minutes_between_api_calls,
+    )
+
     return timedelta(minutes=minutes_between_api_calls)
 
 
 @callback
-def async_reset_coordinator_update_intervals(hass, update_interval):
-    """Update any existing data coordinators with a new update interval."""
-    if not hass.data[DOMAIN][DATA_COORDINATOR]:
-        return
+def async_get_cloud_coordinators_by_api_key(hass, api_key):
+    """Get all DataUpdateCoordinator objects related to a particular API key."""
+    coordinators = []
+    for entry_id, coordinator in hass.data[DOMAIN][DATA_COORDINATOR].items():
+        config_entry = hass.config_entries.async_get_entry(entry_id)
+        if config_entry.data.get(CONF_API_KEY) == api_key:
+            coordinators.append(coordinator)
+    return coordinators
 
-    for coordinator in hass.data[DOMAIN][DATA_COORDINATOR].values():
+
+@callback
+def async_sync_geo_coordinator_update_intervals(hass, api_key):
+    """Sync the update interval for geography-based data coordinators (by API key)."""
+    update_interval = async_get_cloud_api_update_interval(hass, api_key)
+    for coordinator in async_get_cloud_coordinators_by_api_key(hass, api_key):
+        LOGGER.debug(
+            "Updating interval for coordinator: %s, %s",
+            coordinator.name,
+            update_interval,
+        )
         coordinator.update_interval = update_interval
 
 
@@ -194,10 +210,6 @@ async def async_setup_entry(hass, config_entry):
 
         client = Client(api_key=config_entry.data[CONF_API_KEY], session=websession)
 
-        update_interval = async_get_cloud_api_update_interval(
-            hass, config_entry.data[CONF_API_KEY]
-        )
-
         async def async_update_data():
             """Get new data from the API."""
             if CONF_CITY in config_entry.data:
@@ -219,14 +231,19 @@ async def async_setup_entry(hass, config_entry):
         coordinator = DataUpdateCoordinator(
             hass,
             LOGGER,
-            name="geography data",
-            update_interval=update_interval,
+            name=async_get_geography_id(config_entry.data),
+            # We give a placeholder update interval in order to create the coordinator;
+            # then, below, we use the coordinator's presence (along with any other
+            # coordinators using the same API key) to calculate an actual, leveled
+            # update interval:
+            update_interval=timedelta(minutes=5),
             update_method=async_update_data,
         )
 
-        # Ensure any other, existing config entries that use this API key are updated
-        # with the new scan interval:
-        async_reset_coordinator_update_intervals(hass, update_interval)
+        hass.data[DOMAIN][DATA_COORDINATOR][config_entry.entry_id] = coordinator
+        async_sync_geo_coordinator_update_intervals(
+            hass, config_entry.data[CONF_API_KEY]
+        )
 
         # Only geography-based entries have options:
         config_entry.add_update_listener(async_update_options)
@@ -251,13 +268,13 @@ async def async_setup_entry(hass, config_entry):
             hass,
             LOGGER,
             name="Node/Pro data",
-            update_interval=DEFAULT_NODE_PRO_SCAN_INTERVAL,
+            update_interval=DEFAULT_NODE_PRO_UPDATE_INTERVAL,
             update_method=async_update_data,
         )
 
-    await coordinator.async_refresh()
+        hass.data[DOMAIN][DATA_COORDINATOR][config_entry.entry_id] = coordinator
 
-    hass.data[DOMAIN][DATA_COORDINATOR][config_entry.entry_id] = coordinator
+    await coordinator.async_refresh()
 
     for component in PLATFORMS:
         hass.async_create_task(
@@ -317,6 +334,12 @@ async def async_unload_entry(hass, config_entry):
     )
     if unload_ok:
         hass.data[DOMAIN][DATA_COORDINATOR].pop(config_entry.entry_id)
+        if config_entry.data[CONF_INTEGRATION_TYPE] == INTEGRATION_TYPE_GEOGRAPHY:
+            # Re-calculate the update interval period for any remaining consumes of this
+            # API key:
+            async_sync_geo_coordinator_update_intervals(
+                hass, config_entry.data[CONF_API_KEY]
+            )
 
     return unload_ok
 
diff --git a/homeassistant/components/airvisual/air_quality.py b/homeassistant/components/airvisual/air_quality.py
index bd1c10a9d84..bb2d64a23db 100644
--- a/homeassistant/components/airvisual/air_quality.py
+++ b/homeassistant/components/airvisual/air_quality.py
@@ -8,7 +8,7 @@ from .const import (
     CONF_INTEGRATION_TYPE,
     DATA_COORDINATOR,
     DOMAIN,
-    INTEGRATION_TYPE_GEOGRAPHY,
+    INTEGRATION_TYPE_NODE_PRO,
 )
 
 ATTR_HUMIDITY = "humidity"
@@ -18,12 +18,12 @@ ATTR_VOC = "voc"
 
 async def async_setup_entry(hass, config_entry, async_add_entities):
     """Set up AirVisual air quality entities based on a config entry."""
-    coordinator = hass.data[DOMAIN][DATA_COORDINATOR][config_entry.entry_id]
-
     # Geography-based AirVisual integrations don't utilize this platform:
-    if config_entry.data[CONF_INTEGRATION_TYPE] == INTEGRATION_TYPE_GEOGRAPHY:
+    if config_entry.data[CONF_INTEGRATION_TYPE] != INTEGRATION_TYPE_NODE_PRO:
         return
 
+    coordinator = hass.data[DOMAIN][DATA_COORDINATOR][config_entry.entry_id]
+
     async_add_entities([AirVisualNodeProSensor(coordinator)], True)
 
 
diff --git a/homeassistant/components/auth/indieauth.py b/homeassistant/components/auth/indieauth.py
index cd8e797876f..0d942bd358d 100644
--- a/homeassistant/components/auth/indieauth.py
+++ b/homeassistant/components/auth/indieauth.py
@@ -33,8 +33,8 @@ async def verify_redirect_uri(hass, client_id, redirect_uri):
     # Whitelist the iOS and Android callbacks so that people can link apps
     # without being connected to the internet.
     if redirect_uri == "homeassistant://auth-callback" and client_id in (
-        "https://www.home-assistant.io/android",
-        "https://www.home-assistant.io/iOS",
+        "https://home-assistant.io/android",
+        "https://home-assistant.io/iOS",
     ):
         return True
 
diff --git a/homeassistant/components/emulated_hue/const.py b/homeassistant/components/emulated_hue/const.py
new file mode 100644
index 00000000000..bfd58c5a0e1
--- /dev/null
+++ b/homeassistant/components/emulated_hue/const.py
@@ -0,0 +1,4 @@
+"""Constants for emulated_hue."""
+
+HUE_SERIAL_NUMBER = "001788FFFE23BFC2"
+HUE_UUID = "2f402f80-da50-11e1-9b23-001788255acc"
diff --git a/homeassistant/components/emulated_hue/upnp.py b/homeassistant/components/emulated_hue/upnp.py
index f0fe392f865..14e3cf11ca2 100644
--- a/homeassistant/components/emulated_hue/upnp.py
+++ b/homeassistant/components/emulated_hue/upnp.py
@@ -9,6 +9,8 @@ from aiohttp import web
 from homeassistant import core
 from homeassistant.components.http import HomeAssistantView
 
+from .const import HUE_SERIAL_NUMBER, HUE_UUID
+
 _LOGGER = logging.getLogger(__name__)
 
 
@@ -42,8 +44,8 @@ class DescriptionXmlView(HomeAssistantView):
 <modelName>Philips hue bridge 2015</modelName>
 <modelNumber>BSB002</modelNumber>
 <modelURL>http://www.meethue.com</modelURL>
-<serialNumber>001788FFFE23BFC2</serialNumber>
-<UDN>uuid:2f402f80-da50-11e1-9b23-001788255acc</UDN>
+<serialNumber>{HUE_SERIAL_NUMBER}</serialNumber>
+<UDN>uuid:{HUE_UUID}</UDN>
 </device>
 </root>
 """
@@ -70,21 +72,8 @@ class UPNPResponderThread(threading.Thread):
         self.host_ip_addr = host_ip_addr
         self.listen_port = listen_port
         self.upnp_bind_multicast = upnp_bind_multicast
-
-        # Note that the double newline at the end of
-        # this string is required per the SSDP spec
-        resp_template = f"""HTTP/1.1 200 OK
-CACHE-CONTROL: max-age=60
-EXT:
-LOCATION: http://{advertise_ip}:{advertise_port}/description.xml
-SERVER: FreeRTOS/6.0.5, UPnP/1.0, IpBridge/1.16.0
-hue-bridgeid: 001788FFFE23BFC2
-ST: upnp:rootdevice
-USN: uuid:2f402f80-da50-11e1-9b23-00178829d301::upnp:rootdevice
-
-"""
-
-        self.upnp_response = resp_template.replace("\n", "\r\n").encode("utf-8")
+        self.advertise_ip = advertise_ip
+        self.advertise_port = advertise_port
 
     def run(self):
         """Run the server."""
@@ -136,10 +125,13 @@ USN: uuid:2f402f80-da50-11e1-9b23-00178829d301::upnp:rootdevice
                 continue
 
             if "M-SEARCH" in data.decode("utf-8", errors="ignore"):
+                _LOGGER.debug("UPNP Responder M-SEARCH method received: %s", data)
                 # SSDP M-SEARCH method received, respond to it with our info
-                resp_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+                response = self._handle_request(data)
 
-                resp_socket.sendto(self.upnp_response, addr)
+                resp_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+                resp_socket.sendto(response, addr)
+                _LOGGER.debug("UPNP Responder responding with: %s", response)
                 resp_socket.close()
 
     def stop(self):
@@ -148,6 +140,31 @@ USN: uuid:2f402f80-da50-11e1-9b23-00178829d301::upnp:rootdevice
         self._interrupted = True
         self.join()
 
+    def _handle_request(self, data):
+        if "upnp:rootdevice" in data.decode("utf-8", errors="ignore"):
+            return self._prepare_response(
+                "upnp:rootdevice", f"uuid:{HUE_UUID}::upnp:rootdevice"
+            )
+
+        return self._prepare_response(
+            "urn:schemas-upnp-org:device:basic:1", f"uuid:{HUE_UUID}"
+        )
+
+    def _prepare_response(self, search_target, unique_service_name):
+        # Note that the double newline at the end of
+        # this string is required per the SSDP spec
+        response = f"""HTTP/1.1 200 OK
+CACHE-CONTROL: max-age=60
+EXT:
+LOCATION: http://{self.advertise_ip}:{self.advertise_port}/description.xml
+SERVER: FreeRTOS/6.0.5, UPnP/1.0, IpBridge/1.16.0
+hue-bridgeid: {HUE_SERIAL_NUMBER}
+ST: {search_target}
+USN: {unique_service_name}
+
+"""
+        return response.replace("\n", "\r\n").encode("utf-8")
+
 
 def clean_socket_close(sock):
     """Close a socket connection and logs its closure."""
diff --git a/homeassistant/components/frontend/manifest.json b/homeassistant/components/frontend/manifest.json
index 89f83d8fa65..14ae15dd87b 100644
--- a/homeassistant/components/frontend/manifest.json
+++ b/homeassistant/components/frontend/manifest.json
@@ -2,7 +2,7 @@
   "domain": "frontend",
   "name": "Home Assistant Frontend",
   "documentation": "https://www.home-assistant.io/integrations/frontend",
-  "requirements": ["home-assistant-frontend==20200519.4"],
+  "requirements": ["home-assistant-frontend==20200519.5"],
   "dependencies": [
     "api",
     "auth",
diff --git a/homeassistant/components/homekit/__init__.py b/homeassistant/components/homekit/__init__.py
index adbf79128e3..428f8e30abf 100644
--- a/homeassistant/components/homekit/__init__.py
+++ b/homeassistant/components/homekit/__init__.py
@@ -2,6 +2,7 @@
 import asyncio
 import ipaddress
 import logging
+import os
 
 from aiohttp import web
 import voluptuous as vol
@@ -49,6 +50,7 @@ from .const import (
     ATTR_SOFTWARE_VERSION,
     ATTR_VALUE,
     BRIDGE_NAME,
+    BRIDGE_SERIAL_NUMBER,
     CONF_ADVERTISE_IP,
     CONF_AUTO_START,
     CONF_ENTITY_CONFIG,
@@ -434,6 +436,13 @@ class HomeKit:
             interface_choice=self._interface_choice,
         )
 
+        # If we do not load the mac address will be wrong
+        # as pyhap uses a random one until state is restored
+        if os.path.exists(persist_file):
+            self.driver.load()
+        else:
+            self.driver.persist()
+
         self.bridge = HomeBridge(self.hass, self.driver, self._name)
         if self._safe_mode:
             _LOGGER.debug("Safe_mode selected for %s", self._name)
@@ -540,16 +549,45 @@ class HomeKit:
     @callback
     def _async_register_bridge(self, dev_reg):
         """Register the bridge as a device so homekit_controller and exclude it from discovery."""
+        formatted_mac = device_registry.format_mac(self.driver.state.mac)
+        # Connections and identifiers are both used here.
+        #
+        # connections exists so homekit_controller can know the
+        # virtual mac address of the bridge and know to not offer
+        # it via discovery.
+        #
+        # identifiers is used as well since the virtual mac may change
+        # because it will not survive manual pairing resets (deleting state file)
+        # which we have trained users to do over the past few years
+        # because this was the way you had to fix homekit when pairing
+        # failed.
+        #
+        connection = (device_registry.CONNECTION_NETWORK_MAC, formatted_mac)
+        identifier = (DOMAIN, self._entry_id, BRIDGE_SERIAL_NUMBER)
+        self._async_purge_old_bridges(dev_reg, identifier, connection)
         dev_reg.async_get_or_create(
             config_entry_id=self._entry_id,
-            connections={
-                (device_registry.CONNECTION_NETWORK_MAC, self.driver.state.mac)
-            },
+            identifiers={identifier},
+            connections={connection},
             manufacturer=MANUFACTURER,
             name=self._name,
             model="Home Assistant HomeKit Bridge",
         )
 
+    @callback
+    def _async_purge_old_bridges(self, dev_reg, identifier, connection):
+        """Purge bridges that exist from failed pairing or manual resets."""
+        devices_to_purge = []
+        for entry in dev_reg.devices.values():
+            if self._entry_id in entry.config_entries and (
+                identifier not in entry.identifiers
+                or connection not in entry.connections
+            ):
+                devices_to_purge.append(entry.id)
+
+        for device_id in devices_to_purge:
+            dev_reg.async_remove_device(device_id)
+
     def _start(self, bridged_states):
         from . import (  # noqa: F401 pylint: disable=unused-import, import-outside-toplevel
             type_cameras,
diff --git a/homeassistant/components/hunterdouglas_powerview/cover.py b/homeassistant/components/hunterdouglas_powerview/cover.py
index 8135b4a8c77..ea56d56352a 100644
--- a/homeassistant/components/hunterdouglas_powerview/cover.py
+++ b/homeassistant/components/hunterdouglas_powerview/cover.py
@@ -28,6 +28,7 @@ from .const import (
     DEVICE_INFO,
     DEVICE_MODEL,
     DOMAIN,
+    LEGACY_DEVICE_MODEL,
     PV_API,
     PV_ROOM_DATA,
     PV_SHADE_DATA,
@@ -118,7 +119,7 @@ class PowerViewShade(ShadeEntity, CoverEntity):
     def supported_features(self):
         """Flag supported features."""
         supported_features = SUPPORT_OPEN | SUPPORT_CLOSE | SUPPORT_SET_POSITION
-        if self._device_info[DEVICE_MODEL] != "1":
+        if self._device_info[DEVICE_MODEL] != LEGACY_DEVICE_MODEL:
             supported_features |= SUPPORT_STOP
         return supported_features
 
diff --git a/homeassistant/components/iaqualink/manifest.json b/homeassistant/components/iaqualink/manifest.json
index d9d16038d19..68b4554f73a 100644
--- a/homeassistant/components/iaqualink/manifest.json
+++ b/homeassistant/components/iaqualink/manifest.json
@@ -4,5 +4,5 @@
   "config_flow": true,
   "documentation": "https://www.home-assistant.io/integrations/iaqualink/",
   "codeowners": ["@flz"],
-  "requirements": ["iaqualink==0.3.1"]
+  "requirements": ["iaqualink==0.3.3"]
 }
diff --git a/homeassistant/components/iaqualink/sensor.py b/homeassistant/components/iaqualink/sensor.py
index 81021d0b447..80f18dc8191 100644
--- a/homeassistant/components/iaqualink/sensor.py
+++ b/homeassistant/components/iaqualink/sensor.py
@@ -34,16 +34,25 @@ class HassAqualinkSensor(AqualinkEntity):
         return self.dev.label
 
     @property
-    def unit_of_measurement(self) -> str:
+    def unit_of_measurement(self) -> Optional[str]:
         """Return the measurement unit for the sensor."""
-        if self.dev.system.temp_unit == "F":
-            return TEMP_FAHRENHEIT
-        return TEMP_CELSIUS
+        if self.dev.name.endswith("_temp"):
+            if self.dev.system.temp_unit == "F":
+                return TEMP_FAHRENHEIT
+            return TEMP_CELSIUS
+        return None
 
     @property
-    def state(self) -> str:
+    def state(self) -> Optional[str]:
         """Return the state of the sensor."""
-        return int(self.dev.state) if self.dev.state != "" else None
+        if self.dev.state == "":
+            return None
+
+        try:
+            state = int(self.dev.state)
+        except ValueError:
+            state = float(self.dev.state)
+        return state
 
     @property
     def device_class(self) -> Optional[str]:
diff --git a/homeassistant/components/imap_email_content/sensor.py b/homeassistant/components/imap_email_content/sensor.py
index ea93c2bb975..21b535450a1 100644
--- a/homeassistant/components/imap_email_content/sensor.py
+++ b/homeassistant/components/imap_email_content/sensor.py
@@ -103,6 +103,8 @@ class EmailReader:
 
         if message_data is None:
             return None
+        if message_data[0] is None:
+            return None
         raw_email = message_data[0][1]
         email_message = email.message_from_bytes(raw_email)
         return email_message
@@ -126,13 +128,22 @@ class EmailReader:
                     self._last_id = int(message_uid)
                     return self._fetch_message(message_uid)
 
+            return self._fetch_message(str(self._last_id))
+
         except imaplib.IMAP4.error:
             _LOGGER.info("Connection to %s lost, attempting to reconnect", self._server)
             try:
                 self.connect()
+                _LOGGER.info(
+                    "Reconnect to %s succeeded, trying last message", self._server
+                )
+                if self._last_id is not None:
+                    return self._fetch_message(str(self._last_id))
             except imaplib.IMAP4.error:
                 _LOGGER.error("Failed to reconnect")
 
+        return None
+
 
 class EmailContentSensor(Entity):
     """Representation of an EMail sensor."""
diff --git a/homeassistant/components/onvif/base.py b/homeassistant/components/onvif/base.py
index 43a846cac37..cca84c4562a 100644
--- a/homeassistant/components/onvif/base.py
+++ b/homeassistant/components/onvif/base.py
@@ -2,6 +2,7 @@
 from homeassistant.helpers.device_registry import CONNECTION_NETWORK_MAC
 from homeassistant.helpers.entity import Entity
 
+from .const import DOMAIN
 from .device import ONVIFDevice
 from .models import Profile
 
@@ -11,8 +12,8 @@ class ONVIFBaseEntity(Entity):
 
     def __init__(self, device: ONVIFDevice, profile: Profile = None) -> None:
         """Initialize the ONVIF entity."""
-        self.device = device
-        self.profile = profile
+        self.device: ONVIFDevice = device
+        self.profile: Profile = profile
 
     @property
     def available(self):
@@ -22,10 +23,25 @@ class ONVIFBaseEntity(Entity):
     @property
     def device_info(self):
         """Return a device description for device registry."""
-        return {
-            "connections": {(CONNECTION_NETWORK_MAC, self.device.info.mac)},
+        device_info = {
             "manufacturer": self.device.info.manufacturer,
             "model": self.device.info.model,
             "name": self.device.name,
             "sw_version": self.device.info.fw_version,
         }
+
+        # MAC address is not always available, and given the number
+        # of non-conformant ONVIF devices we have historically supported,
+        # we can not guarantee serial number either.  Due to this, we have
+        # adopted an either/or approach in the config entry setup, and can
+        # guarantee that one or the other will be populated.
+        # See: https://github.com/home-assistant/core/issues/35883
+        if self.device.info.serial_number:
+            device_info["identifiers"] = {(DOMAIN, self.device.info.serial_number)}
+
+        if self.device.info.mac:
+            device_info["connections"] = {
+                (CONNECTION_NETWORK_MAC, self.device.info.mac)
+            }
+
+        return device_info
diff --git a/homeassistant/components/onvif/camera.py b/homeassistant/components/onvif/camera.py
index 570b99bfe3a..7f97e0fbea4 100644
--- a/homeassistant/components/onvif/camera.py
+++ b/homeassistant/components/onvif/camera.py
@@ -96,8 +96,8 @@ class ONVIFCameraEntity(ONVIFBaseEntity, Camera):
     def unique_id(self) -> str:
         """Return a unique ID."""
         if self.profile.index:
-            return f"{self.device.info.mac}_{self.profile.index}"
-        return self.device.info.mac
+            return f"{self.device.info.mac or self.device.info.serial_number}_{self.profile.index}"
+        return self.device.info.mac or self.device.info.serial_number
 
     @property
     def entity_registry_enabled_default(self) -> bool:
diff --git a/homeassistant/components/onvif/config_flow.py b/homeassistant/components/onvif/config_flow.py
index 1dba697380d..29784b25429 100644
--- a/homeassistant/components/onvif/config_flow.py
+++ b/homeassistant/components/onvif/config_flow.py
@@ -169,10 +169,16 @@ class OnvifFlowHandler(config_entries.ConfigFlow, domain=DOMAIN):
             self.onvif_config[CONF_PASSWORD] = user_input[CONF_PASSWORD]
             return await self.async_step_profiles()
 
+        # Password is optional and default empty due to some cameras not
+        # allowing you to change ONVIF user settings.
+        # See https://github.com/home-assistant/core/issues/35904
         return self.async_show_form(
             step_id="auth",
             data_schema=vol.Schema(
-                {vol.Required(CONF_USERNAME): str, vol.Required(CONF_PASSWORD): str}
+                {
+                    vol.Required(CONF_USERNAME): str,
+                    vol.Optional(CONF_PASSWORD, default=""): str,
+                }
             ),
         )
 
@@ -195,15 +201,21 @@ class OnvifFlowHandler(config_entries.ConfigFlow, domain=DOMAIN):
         await device.update_xaddrs()
 
         try:
+            device_mgmt = device.create_devicemgmt_service()
+
             # Get the MAC address to use as the unique ID for the config flow
             if not self.device_id:
-                devicemgmt = device.create_devicemgmt_service()
-                network_interfaces = await devicemgmt.GetNetworkInterfaces()
+                network_interfaces = await device_mgmt.GetNetworkInterfaces()
                 for interface in network_interfaces:
                     if interface.Enabled:
                         self.device_id = interface.Info.HwAddress
 
-            if self.device_id is None:
+            # If no network interfaces are exposed, fallback to serial number
+            if not self.device_id:
+                device_info = await device_mgmt.GetDeviceInformation()
+                self.device_id = device_info.SerialNumber
+
+            if not self.device_id:
                 return self.async_abort(reason="no_mac")
 
             await self.async_set_unique_id(self.device_id, raise_on_progress=False)
diff --git a/homeassistant/components/onvif/device.py b/homeassistant/components/onvif/device.py
index 938c960080f..0e9d3ddca98 100644
--- a/homeassistant/components/onvif/device.py
+++ b/homeassistant/components/onvif/device.py
@@ -148,12 +148,12 @@ class ONVIFDevice:
     async def async_check_date_and_time(self) -> None:
         """Warns if device and system date not synced."""
         LOGGER.debug("Setting up the ONVIF device management service")
-        devicemgmt = self.device.create_devicemgmt_service()
+        device_mgmt = self.device.create_devicemgmt_service()
 
         LOGGER.debug("Retrieving current device date/time")
         try:
             system_date = dt_util.utcnow()
-            device_time = await devicemgmt.GetSystemDateAndTime()
+            device_time = await device_mgmt.GetSystemDateAndTime()
             if not device_time:
                 LOGGER.debug(
                     """Couldn't get device '%s' date/time.
@@ -212,13 +212,22 @@ class ONVIFDevice:
 
     async def async_get_device_info(self) -> DeviceInfo:
         """Obtain information about this device."""
-        devicemgmt = self.device.create_devicemgmt_service()
-        device_info = await devicemgmt.GetDeviceInformation()
+        device_mgmt = self.device.create_devicemgmt_service()
+        device_info = await device_mgmt.GetDeviceInformation()
+
+        # Grab the last MAC address for backwards compatibility
+        mac = None
+        network_interfaces = await device_mgmt.GetNetworkInterfaces()
+        for interface in network_interfaces:
+            if interface.Enabled:
+                mac = interface.Info.HwAddress
+
         return DeviceInfo(
             device_info.Manufacturer,
             device_info.Model,
             device_info.FirmwareVersion,
-            self.config_entry.unique_id,
+            device_info.SerialNumber,
+            mac,
         )
 
     async def async_get_capabilities(self):
@@ -228,7 +237,7 @@ class ONVIFDevice:
             media_service = self.device.create_media_service()
             media_capabilities = await media_service.GetServiceCapabilities()
             snapshot = media_capabilities and media_capabilities.SnapshotUri
-        except (ONVIFError, Fault):
+        except (ONVIFError, Fault, ServerDisconnectedError):
             pass
 
         pullpoint = False
@@ -415,7 +424,7 @@ class ONVIFDevice:
                         "PTZ preset '%s' does not exist on device '%s'. Available Presets: %s",
                         preset_val,
                         self.name,
-                        profile.ptz.presets.join(", "),
+                        ", ".join(profile.ptz.presets),
                     )
                     return
 
diff --git a/homeassistant/components/onvif/event.py b/homeassistant/components/onvif/event.py
index 183ad0ab532..3888db4fa8e 100644
--- a/homeassistant/components/onvif/event.py
+++ b/homeassistant/components/onvif/event.py
@@ -62,7 +62,8 @@ class EventManager:
     @callback
     def async_remove_listener(self, update_callback: CALLBACK_TYPE) -> None:
         """Remove data update."""
-        self._listeners.remove(update_callback)
+        if update_callback in self._listeners:
+            self._listeners.remove(update_callback)
 
         if not self._listeners and self._unsub_refresh:
             self._unsub_refresh()
@@ -93,6 +94,8 @@ class EventManager:
 
     async def async_stop(self) -> None:
         """Unsubscribe from events."""
+        self._listeners = []
+
         if not self._subscription:
             return
 
@@ -144,6 +147,10 @@ class EventManager:
     async def async_parse_messages(self, messages) -> None:
         """Parse notification message."""
         for msg in messages:
+            # Guard against empty message
+            if not msg.Topic:
+                continue
+
             topic = msg.Topic._value_1
             parser = PARSERS.get(topic)
             if not parser:
diff --git a/homeassistant/components/onvif/models.py b/homeassistant/components/onvif/models.py
index 686d9fecbda..2a129d3bc44 100644
--- a/homeassistant/components/onvif/models.py
+++ b/homeassistant/components/onvif/models.py
@@ -10,6 +10,7 @@ class DeviceInfo:
     manufacturer: str = None
     model: str = None
     fw_version: str = None
+    serial_number: str = None
     mac: str = None
 
 
diff --git a/homeassistant/components/opengarage/cover.py b/homeassistant/components/opengarage/cover.py
index 239697a229c..70b4d8c98ee 100644
--- a/homeassistant/components/opengarage/cover.py
+++ b/homeassistant/components/opengarage/cover.py
@@ -55,7 +55,7 @@ PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
 )
 
 
-def setup_platform(hass, config, add_entities, discovery_info=None):
+async def async_setup_platform(hass, config, async_add_entities, discovery_info=None):
     """Set up the OpenGarage covers."""
     covers = []
     devices = config.get(CONF_COVERS)
@@ -75,7 +75,7 @@ def setup_platform(hass, config, add_entities, discovery_info=None):
 
         covers.append(OpenGarageCover(device_config.get(CONF_NAME), open_garage))
 
-    add_entities(covers, True)
+    async_add_entities(covers, True)
 
 
 class OpenGarageCover(CoverEntity):
diff --git a/homeassistant/components/roku/manifest.json b/homeassistant/components/roku/manifest.json
index 57c64f4c64a..276fe2332f5 100644
--- a/homeassistant/components/roku/manifest.json
+++ b/homeassistant/components/roku/manifest.json
@@ -2,7 +2,7 @@
   "domain": "roku",
   "name": "Roku",
   "documentation": "https://www.home-assistant.io/integrations/roku",
-  "requirements": ["rokuecp==0.4.1"],
+  "requirements": ["rokuecp==0.4.2"],
   "ssdp": [
     {
       "st": "roku:ecp",
diff --git a/homeassistant/components/roku/media_player.py b/homeassistant/components/roku/media_player.py
index 8c92eff3687..0deeb44dbc2 100644
--- a/homeassistant/components/roku/media_player.py
+++ b/homeassistant/components/roku/media_player.py
@@ -171,15 +171,18 @@ class RokuMediaPlayer(RokuEntity, MediaPlayerEntity):
 
     async def async_media_pause(self) -> None:
         """Send pause command."""
-        await self.coordinator.roku.remote("play")
+        if self.state != STATE_STANDBY:
+            await self.coordinator.roku.remote("play")
 
     async def async_media_play(self) -> None:
         """Send play command."""
-        await self.coordinator.roku.remote("play")
+        if self.state != STATE_STANDBY:
+            await self.coordinator.roku.remote("play")
 
     async def async_media_play_pause(self) -> None:
         """Send play/pause command."""
-        await self.coordinator.roku.remote("play")
+        if self.state != STATE_STANDBY:
+            await self.coordinator.roku.remote("play")
 
     async def async_media_previous_track(self) -> None:
         """Send previous track command."""
diff --git a/homeassistant/components/velux/manifest.json b/homeassistant/components/velux/manifest.json
index e6747060da6..73306bca7b5 100644
--- a/homeassistant/components/velux/manifest.json
+++ b/homeassistant/components/velux/manifest.json
@@ -2,6 +2,6 @@
   "domain": "velux",
   "name": "Velux",
   "documentation": "https://www.home-assistant.io/integrations/velux",
-  "requirements": ["pyvlx==0.2.14"],
+  "requirements": ["pyvlx==0.2.16"],
   "codeowners": ["@Julius2342"]
 }
diff --git a/homeassistant/const.py b/homeassistant/const.py
index 8993225f283..da3d94d85b9 100644
--- a/homeassistant/const.py
+++ b/homeassistant/const.py
@@ -1,7 +1,7 @@
 """Constants used by Home Assistant components."""
 MAJOR_VERSION = 0
 MINOR_VERSION = 110
-PATCH_VERSION = "2"
+PATCH_VERSION = "3"
 __short_version__ = f"{MAJOR_VERSION}.{MINOR_VERSION}"
 __version__ = f"{__short_version__}.{PATCH_VERSION}"
 REQUIRED_PYTHON_VER = (3, 7, 0)
diff --git a/homeassistant/package_constraints.txt b/homeassistant/package_constraints.txt
index e8c3550e996..52981f0a1a1 100644
--- a/homeassistant/package_constraints.txt
+++ b/homeassistant/package_constraints.txt
@@ -12,7 +12,7 @@ cryptography==2.9.2
 defusedxml==0.6.0
 distro==1.5.0
 hass-nabucasa==0.34.3
-home-assistant-frontend==20200519.4
+home-assistant-frontend==20200519.5
 importlib-metadata==1.6.0
 jinja2>=2.11.1
 netdisco==2.6.0
diff --git a/requirements_all.txt b/requirements_all.txt
index 3a7bc962114..c1c0323a906 100644
--- a/requirements_all.txt
+++ b/requirements_all.txt
@@ -731,7 +731,7 @@ hole==0.5.1
 holidays==0.10.2
 
 # homeassistant.components.frontend
-home-assistant-frontend==20200519.4
+home-assistant-frontend==20200519.5
 
 # homeassistant.components.zwave
 homeassistant-pyozw==0.1.10
@@ -764,7 +764,7 @@ hydrawiser==0.1.1
 iammeter==0.1.7
 
 # homeassistant.components.iaqualink
-iaqualink==0.3.1
+iaqualink==0.3.3
 
 # homeassistant.components.watson_tts
 ibm-watson==4.0.1
@@ -1802,7 +1802,7 @@ pyvesync==1.1.0
 pyvizio==0.1.47
 
 # homeassistant.components.velux
-pyvlx==0.2.14
+pyvlx==0.2.16
 
 # homeassistant.components.html5
 pywebpush==1.9.2
@@ -1871,7 +1871,7 @@ rjpl==0.3.5
 rocketchat-API==0.6.1
 
 # homeassistant.components.roku
-rokuecp==0.4.1
+rokuecp==0.4.2
 
 # homeassistant.components.roomba
 roombapy==1.6.1
diff --git a/requirements_test_all.txt b/requirements_test_all.txt
index 59a9b17b4a2..8f75c4d8694 100644
--- a/requirements_test_all.txt
+++ b/requirements_test_all.txt
@@ -312,7 +312,7 @@ hole==0.5.1
 holidays==0.10.2
 
 # homeassistant.components.frontend
-home-assistant-frontend==20200519.4
+home-assistant-frontend==20200519.5
 
 # homeassistant.components.zwave
 homeassistant-pyozw==0.1.10
@@ -331,7 +331,7 @@ httplib2==0.10.3
 huawei-lte-api==1.4.12
 
 # homeassistant.components.iaqualink
-iaqualink==0.3.1
+iaqualink==0.3.3
 
 # homeassistant.components.influxdb
 influxdb==5.2.3
@@ -762,7 +762,7 @@ rflink==0.0.52
 ring_doorbell==0.6.0
 
 # homeassistant.components.roku
-rokuecp==0.4.1
+rokuecp==0.4.2
 
 # homeassistant.components.roomba
 roombapy==1.6.1
diff --git a/tests/components/auth/test_indieauth.py b/tests/components/auth/test_indieauth.py
index 3d1ba068c85..8a02502e16c 100644
--- a/tests/components/auth/test_indieauth.py
+++ b/tests/components/auth/test_indieauth.py
@@ -166,8 +166,7 @@ async def test_find_link_tag_max_size(hass, mock_session):
 
 
 @pytest.mark.parametrize(
-    "client_id",
-    ["https://www.home-assistant.io/android", "https://www.home-assistant.io/iOS"],
+    "client_id", ["https://home-assistant.io/android", "https://home-assistant.io/iOS"],
 )
 async def test_verify_redirect_uri_android_ios(client_id):
     """Test that we verify redirect uri correctly for Android/iOS."""
diff --git a/tests/components/emulated_hue/test_upnp.py b/tests/components/emulated_hue/test_upnp.py
index 32859ca00c1..a6040e8db68 100644
--- a/tests/components/emulated_hue/test_upnp.py
+++ b/tests/components/emulated_hue/test_upnp.py
@@ -48,6 +48,66 @@ class TestEmulatedHue(unittest.TestCase):
         """Stop the class."""
         cls.hass.stop()
 
+    def test_upnp_discovery_basic(self):
+        """Tests the UPnP basic discovery response."""
+        with patch("threading.Thread.__init__"):
+            upnp_responder_thread = emulated_hue.UPNPResponderThread(
+                "0.0.0.0", 80, True, "192.0.2.42", 8080
+            )
+
+            """Original request emitted by the Hue Bridge v1 app."""
+            request = """M-SEARCH * HTTP/1.1
+HOST:239.255.255.250:1900
+ST:ssdp:all
+Man:"ssdp:discover"
+MX:3
+
+"""
+            encoded_request = request.replace("\n", "\r\n").encode("utf-8")
+
+            response = upnp_responder_thread._handle_request(encoded_request)
+            expected_response = """HTTP/1.1 200 OK
+CACHE-CONTROL: max-age=60
+EXT:
+LOCATION: http://192.0.2.42:8080/description.xml
+SERVER: FreeRTOS/6.0.5, UPnP/1.0, IpBridge/1.16.0
+hue-bridgeid: 001788FFFE23BFC2
+ST: urn:schemas-upnp-org:device:basic:1
+USN: uuid:2f402f80-da50-11e1-9b23-001788255acc
+
+"""
+            assert expected_response.replace("\n", "\r\n").encode("utf-8") == response
+
+    def test_upnp_discovery_rootdevice(self):
+        """Tests the UPnP rootdevice discovery response."""
+        with patch("threading.Thread.__init__"):
+            upnp_responder_thread = emulated_hue.UPNPResponderThread(
+                "0.0.0.0", 80, True, "192.0.2.42", 8080
+            )
+
+            """Original request emitted by Busch-Jaeger free@home SysAP."""
+            request = """M-SEARCH * HTTP/1.1
+HOST: 239.255.255.250:1900
+MAN: "ssdp:discover"
+MX: 40
+ST: upnp:rootdevice
+
+"""
+            encoded_request = request.replace("\n", "\r\n").encode("utf-8")
+
+            response = upnp_responder_thread._handle_request(encoded_request)
+            expected_response = """HTTP/1.1 200 OK
+CACHE-CONTROL: max-age=60
+EXT:
+LOCATION: http://192.0.2.42:8080/description.xml
+SERVER: FreeRTOS/6.0.5, UPnP/1.0, IpBridge/1.16.0
+hue-bridgeid: 001788FFFE23BFC2
+ST: upnp:rootdevice
+USN: uuid:2f402f80-da50-11e1-9b23-001788255acc::upnp:rootdevice
+
+"""
+            assert expected_response.replace("\n", "\r\n").encode("utf-8") == response
+
     def test_description_xml(self):
         """Test the description."""
         result = requests.get(BRIDGE_URL_BASE.format("/description.xml"), timeout=5)
diff --git a/tests/components/homekit/test_homekit.py b/tests/components/homekit/test_homekit.py
index c0e2ea90fba..b016997b7c9 100644
--- a/tests/components/homekit/test_homekit.py
+++ b/tests/components/homekit/test_homekit.py
@@ -19,6 +19,7 @@ from homeassistant.components.homekit.accessories import HomeBridge
 from homeassistant.components.homekit.const import (
     AID_STORAGE,
     BRIDGE_NAME,
+    BRIDGE_SERIAL_NUMBER,
     CONF_AUTO_START,
     CONF_ENTRY_INDEX,
     CONF_SAFE_MODE,
@@ -458,7 +459,7 @@ async def test_homekit_entity_filter(hass):
         assert mock_get_acc.called is False
 
 
-async def test_homekit_start(hass, hk_driver, debounce_patcher):
+async def test_homekit_start(hass, hk_driver, device_reg, debounce_patcher):
     """Test HomeKit start method."""
     entry = await async_init_integration(hass)
 
@@ -480,6 +481,15 @@ async def test_homekit_start(hass, hk_driver, debounce_patcher):
     homekit.driver = hk_driver
     homekit._filter = Mock(return_value=True)
 
+    connection = (device_registry.CONNECTION_NETWORK_MAC, "AA:BB:CC:DD:EE:FF")
+    bridge_with_wrong_mac = device_reg.async_get_or_create(
+        config_entry_id=entry.entry_id,
+        connections={connection},
+        manufacturer="Any",
+        name="Any",
+        model="Home Assistant HomeKit Bridge",
+    )
+
     hass.states.async_set("light.demo", "on")
     state = hass.states.async_all()[0]
 
@@ -505,6 +515,35 @@ async def test_homekit_start(hass, hk_driver, debounce_patcher):
     await hass.async_block_till_done()
     assert not hk_driver_start.called
 
+    assert device_reg.async_get(bridge_with_wrong_mac.id) is None
+
+    device = device_reg.async_get_device(
+        {(DOMAIN, entry.entry_id, BRIDGE_SERIAL_NUMBER)}, {}
+    )
+    assert device
+    formatted_mac = device_registry.format_mac(homekit.driver.state.mac)
+    assert (device_registry.CONNECTION_NETWORK_MAC, formatted_mac) in device.connections
+
+    # Start again to make sure the registry entry is kept
+    homekit.status = STATUS_READY
+    with patch(f"{PATH_HOMEKIT}.HomeKit.add_bridge_accessory") as mock_add_acc, patch(
+        f"{PATH_HOMEKIT}.show_setup_message"
+    ) as mock_setup_msg, patch(
+        "pyhap.accessory_driver.AccessoryDriver.add_accessory"
+    ) as hk_driver_add_acc, patch(
+        "pyhap.accessory_driver.AccessoryDriver.start"
+    ) as hk_driver_start:
+        await homekit.async_start()
+
+    device = device_reg.async_get_device(
+        {(DOMAIN, entry.entry_id, BRIDGE_SERIAL_NUMBER)}, {}
+    )
+    assert device
+    formatted_mac = device_registry.format_mac(homekit.driver.state.mac)
+    assert (device_registry.CONNECTION_NETWORK_MAC, formatted_mac) in device.connections
+
+    assert len(device_reg.devices) == 1
+
 
 async def test_homekit_start_with_a_broken_accessory(hass, hk_driver, debounce_patcher):
     """Test HomeKit start method."""
diff --git a/tests/components/onvif/test_config_flow.py b/tests/components/onvif/test_config_flow.py
index c709c5e6f67..5c41349bbbe 100644
--- a/tests/components/onvif/test_config_flow.py
+++ b/tests/components/onvif/test_config_flow.py
@@ -1,13 +1,11 @@
 """Test ONVIF config flow."""
-from asyncio import Future
-
-from asynctest import MagicMock, patch
 from onvif.exceptions import ONVIFError
 from zeep.exceptions import Fault
 
 from homeassistant import config_entries, data_entry_flow
 from homeassistant.components.onvif import config_flow
 
+from tests.async_mock import AsyncMock, MagicMock, patch
 from tests.common import MockConfigEntry
 
 URN = "urn:uuid:123456789"
@@ -17,6 +15,7 @@ PORT = 80
 USERNAME = "admin"
 PASSWORD = "12345"
 MAC = "aa:bb:cc:dd:ee"
+SERIAL_NUMBER = "ABCDEFGHIJK"
 
 DISCOVERY = [
     {
@@ -37,18 +36,25 @@ DISCOVERY = [
 
 
 def setup_mock_onvif_camera(
-    mock_onvif_camera, with_h264=True, two_profiles=False, with_interfaces=True
+    mock_onvif_camera,
+    with_h264=True,
+    two_profiles=False,
+    with_interfaces=True,
+    with_serial=True,
 ):
     """Prepare mock onvif.ONVIFCamera."""
     devicemgmt = MagicMock()
 
+    device_info = MagicMock()
+    device_info.SerialNumber = SERIAL_NUMBER if with_serial else None
+    devicemgmt.GetDeviceInformation = AsyncMock(return_value=device_info)
+
     interface = MagicMock()
     interface.Enabled = True
     interface.Info.HwAddress = MAC
 
-    devicemgmt.GetNetworkInterfaces.return_value = Future()
-    devicemgmt.GetNetworkInterfaces.return_value.set_result(
-        [interface] if with_interfaces else []
+    devicemgmt.GetNetworkInterfaces = AsyncMock(
+        return_value=[interface] if with_interfaces else []
     )
 
     media_service = MagicMock()
@@ -58,11 +64,9 @@ def setup_mock_onvif_camera(
     profile2 = MagicMock()
     profile2.VideoEncoderConfiguration.Encoding = "H264" if two_profiles else "MJPEG"
 
-    media_service.GetProfiles.return_value = Future()
-    media_service.GetProfiles.return_value.set_result([profile1, profile2])
+    media_service.GetProfiles = AsyncMock(return_value=[profile1, profile2])
 
-    mock_onvif_camera.update_xaddrs.return_value = Future()
-    mock_onvif_camera.update_xaddrs.return_value.set_result(True)
+    mock_onvif_camera.update_xaddrs = AsyncMock(return_value=True)
     mock_onvif_camera.create_devicemgmt_service = MagicMock(return_value=devicemgmt)
     mock_onvif_camera.create_media_service = MagicMock(return_value=media_service)
 
@@ -116,8 +120,7 @@ def setup_mock_discovery(
 
 def setup_mock_device(mock_device):
     """Prepare mock ONVIFDevice."""
-    mock_device.async_setup.return_value = Future()
-    mock_device.async_setup.return_value.set_result(True)
+    mock_device.async_setup = AsyncMock(return_value=True)
 
     def mock_constructor(hass, config):
         """Fake the controller constructor."""
@@ -390,11 +393,48 @@ async def test_flow_manual_entry(hass):
 
 
 async def test_flow_import_no_mac(hass):
-    """Test that config flow fails when no MAC available."""
+    """Test that config flow uses Serial Number when no MAC available."""
+    with patch(
+        "homeassistant.components.onvif.config_flow.get_device"
+    ) as mock_onvif_camera, patch(
+        "homeassistant.components.onvif.ONVIFDevice"
+    ) as mock_device:
+        setup_mock_onvif_camera(mock_onvif_camera, with_interfaces=False)
+        setup_mock_device(mock_device)
+
+        result = await hass.config_entries.flow.async_init(
+            config_flow.DOMAIN,
+            context={"source": config_entries.SOURCE_IMPORT},
+            data={
+                config_flow.CONF_NAME: NAME,
+                config_flow.CONF_HOST: HOST,
+                config_flow.CONF_PORT: PORT,
+                config_flow.CONF_USERNAME: USERNAME,
+                config_flow.CONF_PASSWORD: PASSWORD,
+            },
+        )
+
+        await hass.async_block_till_done()
+
+        assert result["type"] == data_entry_flow.RESULT_TYPE_CREATE_ENTRY
+        assert result["title"] == f"{NAME} - {SERIAL_NUMBER}"
+        assert result["data"] == {
+            config_flow.CONF_NAME: NAME,
+            config_flow.CONF_HOST: HOST,
+            config_flow.CONF_PORT: PORT,
+            config_flow.CONF_USERNAME: USERNAME,
+            config_flow.CONF_PASSWORD: PASSWORD,
+        }
+
+
+async def test_flow_import_no_mac_or_serial(hass):
+    """Test that config flow fails when no MAC or Serial Number available."""
     with patch(
         "homeassistant.components.onvif.config_flow.get_device"
     ) as mock_onvif_camera:
-        setup_mock_onvif_camera(mock_onvif_camera, with_interfaces=False)
+        setup_mock_onvif_camera(
+            mock_onvif_camera, with_interfaces=False, with_serial=False
+        )
 
         result = await hass.config_entries.flow.async_init(
             config_flow.DOMAIN,