diff --git a/common/protob/messages-management.proto b/common/protob/messages-management.proto
index bf19c94f4e..8b7f0b215d 100644
--- a/common/protob/messages-management.proto
+++ b/common/protob/messages-management.proto
@@ -227,7 +227,7 @@ message LoadDevice {
     repeated string mnemonics = 1;                          // seed encoded as mnemonic (12, 18 or 24 words for BIP39, 20 or 33 for SLIP39)
     optional string pin = 3;                                // set PIN protection
     optional bool passphrase_protection = 4;                // enable master node encryption using passphrase
-    optional string language = 5 [default='english'];       // device language
+    optional string language = 5 [default='en-US'];         // device language (IETF BCP 47 language tag)
     optional string label = 6;                              // device label
     optional bool skip_checksum = 7;                        // do not test mnemonic for valid BIP-39 checksum
     optional uint32 u2f_counter = 8;                        // U2F counter
@@ -246,7 +246,7 @@ message ResetDevice {
     optional uint32 strength = 2 [default=256];             // strength of seed in bits
     optional bool passphrase_protection = 3;                // enable master node encryption using passphrase
     optional bool pin_protection = 4;                       // enable PIN protection
-    optional string language = 5 [default='english'];       // device language
+    optional string language = 5 [default='en-US'];         // device language (IETF BCP 47 language tag)
     optional string label = 6;                              // device label
     optional uint32 u2f_counter = 7;                        // U2F counter
     optional bool skip_backup = 8;                          // postpone seed backup to BackupDevice workflow
@@ -287,7 +287,7 @@ message RecoveryDevice {
     optional uint32 word_count = 1;                     // number of words in BIP-39 mnemonic
     optional bool passphrase_protection = 2;            // enable master node encryption using passphrase
     optional bool pin_protection = 3;                   // enable PIN protection
-    optional string language = 4 [default='english'];   // device language
+    optional string language = 4 [default='en-US'];     // device language (IETF BCP 47 language tag)
     optional string label = 5;                          // device label
     optional bool enforce_wordlist = 6;                 // enforce BIP-39 wordlist during the process
     // 7 reserved for unused recovery method
diff --git a/core/src/apps/homescreen/__init__.py b/core/src/apps/homescreen/__init__.py
index 59669706ea..db711fd117 100644
--- a/core/src/apps/homescreen/__init__.py
+++ b/core/src/apps/homescreen/__init__.py
@@ -23,7 +23,7 @@ if False:
 def get_features() -> Features:
     f = Features()
     f.vendor = "trezor.io"
-    f.language = "english"
+    f.language = "en-US"
     f.major_version = utils.VERSION_MAJOR
     f.minor_version = utils.VERSION_MINOR
     f.patch_version = utils.VERSION_PATCH
diff --git a/core/src/trezor/messages/LoadDevice.py b/core/src/trezor/messages/LoadDevice.py
index a9d19c2ffc..18ebd512af 100644
--- a/core/src/trezor/messages/LoadDevice.py
+++ b/core/src/trezor/messages/LoadDevice.py
@@ -41,7 +41,7 @@ class LoadDevice(p.MessageType):
             1: ('mnemonics', p.UnicodeType, p.FLAG_REPEATED),
             3: ('pin', p.UnicodeType, 0),
             4: ('passphrase_protection', p.BoolType, 0),
-            5: ('language', p.UnicodeType, 0),  # default=english
+            5: ('language', p.UnicodeType, 0),  # default=en-US
             6: ('label', p.UnicodeType, 0),
             7: ('skip_checksum', p.BoolType, 0),
             8: ('u2f_counter', p.UVarintType, 0),
diff --git a/core/src/trezor/messages/RecoveryDevice.py b/core/src/trezor/messages/RecoveryDevice.py
index 2aab379095..0d12b80043 100644
--- a/core/src/trezor/messages/RecoveryDevice.py
+++ b/core/src/trezor/messages/RecoveryDevice.py
@@ -42,7 +42,7 @@ class RecoveryDevice(p.MessageType):
             1: ('word_count', p.UVarintType, 0),
             2: ('passphrase_protection', p.BoolType, 0),
             3: ('pin_protection', p.BoolType, 0),
-            4: ('language', p.UnicodeType, 0),  # default=english
+            4: ('language', p.UnicodeType, 0),  # default=en-US
             5: ('label', p.UnicodeType, 0),
             6: ('enforce_wordlist', p.BoolType, 0),
             8: ('type', p.EnumType("RecoveryDeviceType", (0, 1)), 0),
diff --git a/core/src/trezor/messages/ResetDevice.py b/core/src/trezor/messages/ResetDevice.py
index abe192ae1f..3e32b64bcf 100644
--- a/core/src/trezor/messages/ResetDevice.py
+++ b/core/src/trezor/messages/ResetDevice.py
@@ -45,7 +45,7 @@ class ResetDevice(p.MessageType):
             2: ('strength', p.UVarintType, 0),  # default=256
             3: ('passphrase_protection', p.BoolType, 0),
             4: ('pin_protection', p.BoolType, 0),
-            5: ('language', p.UnicodeType, 0),  # default=english
+            5: ('language', p.UnicodeType, 0),  # default=en-US
             6: ('label', p.UnicodeType, 0),
             7: ('u2f_counter', p.UVarintType, 0),
             8: ('skip_backup', p.BoolType, 0),
diff --git a/legacy/firmware/config.c b/legacy/firmware/config.c
index 98a1e907b7..485ac8616b 100644
--- a/legacy/firmware/config.c
+++ b/legacy/firmware/config.c
@@ -520,7 +520,7 @@ void config_setLanguage(const char *lang) {
   }
 
   // Sanity check.
-  if (strcmp(lang, "english") != 0) {
+  if (strcmp(lang, "en-US") != 0) {
     return;
   }
   storage_set(KEY_LANGUAGE, lang, strnlen(lang, MAX_LANGUAGE_LEN));
@@ -665,7 +665,17 @@ bool config_getLabel(char *dest, uint16_t dest_size) {
 }
 
 bool config_getLanguage(char *dest, uint16_t dest_size) {
-  return sectrue == config_get_string(KEY_LANGUAGE, dest, dest_size);
+  if (sectrue == config_get_string(KEY_LANGUAGE, dest, dest_size)) {
+    if (dest_size == 7 && (strcmp(dest, "english") != 0)) {
+      // fallthrough -> return "en-US"
+    } else {
+      // other language -> return the value
+      return true;
+    }
+  }
+  strcpy(dest, "en-US");
+  dest_size = 5;
+  return true;
 }
 
 bool config_getHomescreen(uint8_t *dest, uint16_t dest_size) {
diff --git a/python/src/trezorlib/cli/device.py b/python/src/trezorlib/cli/device.py
index 8f9557c865..be79f85345 100644
--- a/python/src/trezorlib/cli/device.py
+++ b/python/src/trezorlib/cli/device.py
@@ -129,7 +129,7 @@ def load(
         pin=pin,
         passphrase_protection=passphrase_protection,
         label=label,
-        language="english",
+        language="en-US",
         skip_checksum=ignore_checksum,
         needs_backup=needs_backup,
         no_backup=no_backup,
@@ -170,7 +170,7 @@ def recover(
         passphrase_protection=passphrase_protection,
         pin_protection=pin_protection,
         label=label,
-        language="english",
+        language="en-US",
         input_callback=input_callback,
         type=rec_type,
         dry_run=dry_run,
@@ -224,7 +224,7 @@ def setup(
         passphrase_protection=passphrase_protection,
         pin_protection=pin_protection,
         label=label,
-        language="english",
+        language="en-US",
         u2f_counter=u2f_counter,
         skip_backup=skip_backup,
         no_backup=no_backup,
diff --git a/python/src/trezorlib/debuglink.py b/python/src/trezorlib/debuglink.py
index d0a4c66767..ff7721c532 100644
--- a/python/src/trezorlib/debuglink.py
+++ b/python/src/trezorlib/debuglink.py
@@ -456,7 +456,7 @@ def load_device(
     pin,
     passphrase_protection,
     label,
-    language="english",
+    language="en-US",
     skip_checksum=False,
     needs_backup=False,
     no_backup=False,
diff --git a/python/src/trezorlib/device.py b/python/src/trezorlib/device.py
index f95836137f..ddd89ba2b0 100644
--- a/python/src/trezorlib/device.py
+++ b/python/src/trezorlib/device.py
@@ -117,7 +117,7 @@ def recover(
     passphrase_protection=False,
     pin_protection=True,
     label=None,
-    language="english",
+    language="en-US",
     input_callback=None,
     type=messages.RecoveryDeviceType.ScrambledWords,
     dry_run=False,
@@ -171,7 +171,7 @@ def reset(
     passphrase_protection=False,
     pin_protection=True,
     label=None,
-    language="english",
+    language="en-US",
     u2f_counter=0,
     skip_backup=False,
     no_backup=False,
diff --git a/python/src/trezorlib/messages/LoadDevice.py b/python/src/trezorlib/messages/LoadDevice.py
index d9eef5e7fa..0226453afd 100644
--- a/python/src/trezorlib/messages/LoadDevice.py
+++ b/python/src/trezorlib/messages/LoadDevice.py
@@ -41,7 +41,7 @@ class LoadDevice(p.MessageType):
             1: ('mnemonics', p.UnicodeType, p.FLAG_REPEATED),
             3: ('pin', p.UnicodeType, 0),
             4: ('passphrase_protection', p.BoolType, 0),
-            5: ('language', p.UnicodeType, 0),  # default=english
+            5: ('language', p.UnicodeType, 0),  # default=en-US
             6: ('label', p.UnicodeType, 0),
             7: ('skip_checksum', p.BoolType, 0),
             8: ('u2f_counter', p.UVarintType, 0),
diff --git a/python/src/trezorlib/messages/RecoveryDevice.py b/python/src/trezorlib/messages/RecoveryDevice.py
index 4f94b43fba..380b032602 100644
--- a/python/src/trezorlib/messages/RecoveryDevice.py
+++ b/python/src/trezorlib/messages/RecoveryDevice.py
@@ -42,7 +42,7 @@ class RecoveryDevice(p.MessageType):
             1: ('word_count', p.UVarintType, 0),
             2: ('passphrase_protection', p.BoolType, 0),
             3: ('pin_protection', p.BoolType, 0),
-            4: ('language', p.UnicodeType, 0),  # default=english
+            4: ('language', p.UnicodeType, 0),  # default=en-US
             5: ('label', p.UnicodeType, 0),
             6: ('enforce_wordlist', p.BoolType, 0),
             8: ('type', p.EnumType("RecoveryDeviceType", (0, 1)), 0),
diff --git a/python/src/trezorlib/messages/ResetDevice.py b/python/src/trezorlib/messages/ResetDevice.py
index e4b588c6d2..123f55a318 100644
--- a/python/src/trezorlib/messages/ResetDevice.py
+++ b/python/src/trezorlib/messages/ResetDevice.py
@@ -45,7 +45,7 @@ class ResetDevice(p.MessageType):
             2: ('strength', p.UVarintType, 0),  # default=256
             3: ('passphrase_protection', p.BoolType, 0),
             4: ('pin_protection', p.BoolType, 0),
-            5: ('language', p.UnicodeType, 0),  # default=english
+            5: ('language', p.UnicodeType, 0),  # default=en-US
             6: ('label', p.UnicodeType, 0),
             7: ('u2f_counter', p.UVarintType, 0),
             8: ('skip_backup', p.BoolType, 0),
diff --git a/tests/conftest.py b/tests/conftest.py
index 49fea36bf0..ed13e96c00 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -116,7 +116,7 @@ def client(request):
             pin=setup_params["pin"],
             passphrase_protection=setup_params["passphrase"],
             label="test",
-            language="english",
+            language="en-US",
             needs_backup=setup_params["needs_backup"],
             no_backup=setup_params["no_backup"],
         )
diff --git a/tests/device_tests/test_msg_applysettings.py b/tests/device_tests/test_msg_applysettings.py
index 7acee541a4..c9f83063aa 100644
--- a/tests/device_tests/test_msg_applysettings.py
+++ b/tests/device_tests/test_msg_applysettings.py
@@ -44,13 +44,13 @@ class TestMsgApplysettings:
 
     @pytest.mark.skip_t2
     def test_invalid_language(self, client):
-        assert client.features.language == "english"
+        assert client.features.language == "en-US"
 
         with client:
             _set_expected_responses(client)
             device.apply_settings(client, language="nonexistent")
 
-        assert client.features.language == "english"
+        assert client.features.language == "en-US"
 
     @pytest.mark.setup_client(pin=True, passphrase=False)
     def test_apply_settings_passphrase(self, client):
diff --git a/tests/device_tests/test_msg_backup_device.py b/tests/device_tests/test_msg_backup_device.py
index c0138c4cfd..f605b9ff49 100644
--- a/tests/device_tests/test_msg_backup_device.py
+++ b/tests/device_tests/test_msg_backup_device.py
@@ -306,6 +306,6 @@ def test_no_backup_show_entropy_fails(client):
             passphrase_protection=False,
             pin_protection=False,
             label="test",
-            language="english",
+            language="en-US",
             no_backup=True,
         )
diff --git a/tests/device_tests/test_msg_cardano_get_address.py b/tests/device_tests/test_msg_cardano_get_address.py
index d7429e1219..22cefe1152 100644
--- a/tests/device_tests/test_msg_cardano_get_address.py
+++ b/tests/device_tests/test_msg_cardano_get_address.py
@@ -44,7 +44,6 @@ from ..common import MNEMONIC12
 )
 @pytest.mark.setup_client(mnemonic=MNEMONIC12)
 def test_cardano_get_address(client, path, expected_address):
-    # data from https://iancoleman.io/bip39/#english
-
+    # data from https://iancoleman.io/bip39/
     address = get_address(client, parse_path(path))
     assert address == expected_address
diff --git a/tests/device_tests/test_msg_loaddevice.py b/tests/device_tests/test_msg_loaddevice.py
index 388f436a2b..e308a4216f 100644
--- a/tests/device_tests/test_msg_loaddevice.py
+++ b/tests/device_tests/test_msg_loaddevice.py
@@ -115,7 +115,7 @@ class TestDeviceLoad:
             pin="",
             passphrase_protection=True,
             label="test",
-            language="english",
+            language="en-US",
             skip_checksum=True,
         )
         if client.features.model == "T":
@@ -130,7 +130,7 @@ class TestDeviceLoad:
             pin="",
             passphrase_protection=True,
             label="test",
-            language="english",
+            language="en-US",
             skip_checksum=True,
         )
         if client.features.model == "T":
@@ -145,7 +145,7 @@ class TestDeviceLoad:
             pin="",
             passphrase_protection=True,
             label="test",
-            language="english",
+            language="en-US",
             skip_checksum=True,
         )
         if client.features.model == "T":
@@ -160,7 +160,7 @@ class TestDeviceLoad:
             pin="",
             passphrase_protection=True,
             label="test",
-            language="english",
+            language="en-US",
             skip_checksum=True,
         )
         if client.features.model == "T":
diff --git a/tests/device_tests/test_msg_recoverydevice_bip39.py b/tests/device_tests/test_msg_recoverydevice_bip39.py
index 6861c57003..69e78f1372 100644
--- a/tests/device_tests/test_msg_recoverydevice_bip39.py
+++ b/tests/device_tests/test_msg_recoverydevice_bip39.py
@@ -35,7 +35,7 @@ class TestMsgRecoverydevice:
                 passphrase_protection=True,
                 pin_protection=True,
                 label="label",
-                language="english",
+                language="en-US",
                 enforce_wordlist=True,
             )
         )
@@ -98,7 +98,7 @@ class TestMsgRecoverydevice:
                 passphrase_protection=False,
                 pin_protection=False,
                 label="label",
-                language="english",
+                language="en-US",
                 enforce_wordlist=True,
             )
         )
@@ -152,7 +152,7 @@ class TestMsgRecoverydevice:
                 passphrase_protection=False,
                 pin_protection=False,
                 label="label",
-                language="english",
+                language="en-US",
                 enforce_wordlist=True,
             )
         )
@@ -180,7 +180,7 @@ class TestMsgRecoverydevice:
                 passphrase_protection=True,
                 pin_protection=True,
                 label="label",
-                language="english",
+                language="en-US",
                 enforce_wordlist=True,
             )
         )
@@ -207,5 +207,5 @@ class TestMsgRecoverydevice:
     def test_already_initialized(self, client):
         with pytest.raises(RuntimeError):
             device.recover(
-                client, 12, False, False, "label", "english", client.mnemonic_callback
+                client, 12, False, False, "label", "en-US", client.mnemonic_callback
             )
diff --git a/tests/device_tests/test_msg_recoverydevice_bip39_t2.py b/tests/device_tests/test_msg_recoverydevice_bip39_t2.py
index d734f7ec42..79d516e215 100644
--- a/tests/device_tests/test_msg_recoverydevice_bip39_t2.py
+++ b/tests/device_tests/test_msg_recoverydevice_bip39_t2.py
@@ -149,5 +149,5 @@ class TestMsgRecoverydeviceT2:
     def test_already_initialized(self, client):
         with pytest.raises(RuntimeError):
             device.recover(
-                client, 12, False, False, "label", "english", client.mnemonic_callback
+                client, 12, False, False, "label", "en-US", client.mnemonic_callback
             )
diff --git a/tests/device_tests/test_msg_recoverydevice_slip39_advanced_dryrun.py b/tests/device_tests/test_msg_recoverydevice_slip39_advanced_dryrun.py
index 29d62e6d91..f170002d83 100644
--- a/tests/device_tests/test_msg_recoverydevice_slip39_advanced_dryrun.py
+++ b/tests/device_tests/test_msg_recoverydevice_slip39_advanced_dryrun.py
@@ -55,7 +55,7 @@ def test_2of3_dryrun(client):
             passphrase_protection=False,
             pin_protection=False,
             label="label",
-            language="english",
+            language="en-US",
             dry_run=True,
         )
 
@@ -87,6 +87,6 @@ def test_2of3_invalid_seed_dryrun(client):
             passphrase_protection=False,
             pin_protection=False,
             label="label",
-            language="english",
+            language="en-US",
             dry_run=True,
         )
diff --git a/tests/device_tests/test_msg_recoverydevice_slip39_basic_dryrun.py b/tests/device_tests/test_msg_recoverydevice_slip39_basic_dryrun.py
index 0a8b3564f1..e2238116d1 100644
--- a/tests/device_tests/test_msg_recoverydevice_slip39_basic_dryrun.py
+++ b/tests/device_tests/test_msg_recoverydevice_slip39_basic_dryrun.py
@@ -52,7 +52,7 @@ def test_2of3_dryrun(client):
             passphrase_protection=False,
             pin_protection=False,
             label="label",
-            language="english",
+            language="en-US",
             dry_run=True,
         )
 
@@ -82,6 +82,6 @@ def test_2of3_invalid_seed_dryrun(client):
             passphrase_protection=False,
             pin_protection=False,
             label="label",
-            language="english",
+            language="en-US",
             dry_run=True,
         )
diff --git a/tests/device_tests/test_msg_resetdevice_bip39.py b/tests/device_tests/test_msg_resetdevice_bip39.py
index 7cba9cdb00..4606efed94 100644
--- a/tests/device_tests/test_msg_resetdevice_bip39.py
+++ b/tests/device_tests/test_msg_resetdevice_bip39.py
@@ -36,7 +36,7 @@ class TestMsgResetDevice:
                 strength=strength,
                 passphrase_protection=False,
                 pin_protection=False,
-                language="english",
+                language="en-US",
                 label="test",
             )
         )
@@ -106,7 +106,7 @@ class TestMsgResetDevice:
                 strength=strength,
                 passphrase_protection=True,
                 pin_protection=True,
-                language="english",
+                language="en-US",
                 label="test",
             )
         )
@@ -195,7 +195,7 @@ class TestMsgResetDevice:
                 strength=strength,
                 passphrase_protection=True,
                 pin_protection=True,
-                language="english",
+                language="en-US",
                 label="test",
             )
         )
@@ -230,4 +230,4 @@ class TestMsgResetDevice:
 
     def test_already_initialized(self, client):
         with pytest.raises(Exception):
-            device.reset(client, False, 128, True, True, "label", "english")
+            device.reset(client, False, 128, True, True, "label", "en-US")
diff --git a/tests/device_tests/test_msg_resetdevice_bip39_skipbackup.py b/tests/device_tests/test_msg_resetdevice_bip39_skipbackup.py
index a50455d2c7..366a4247ec 100644
--- a/tests/device_tests/test_msg_resetdevice_bip39_skipbackup.py
+++ b/tests/device_tests/test_msg_resetdevice_bip39_skipbackup.py
@@ -36,7 +36,7 @@ class TestMsgResetDeviceSkipbackup:
                 strength=self.strength,
                 passphrase_protection=False,
                 pin_protection=False,
-                language="english",
+                language="en-US",
                 label="test",
                 skip_backup=True,
             )
@@ -106,7 +106,7 @@ class TestMsgResetDeviceSkipbackup:
                 strength=self.strength,
                 passphrase_protection=False,
                 pin_protection=False,
-                language="english",
+                language="en-US",
                 label="test",
                 skip_backup=True,
             )
@@ -163,7 +163,7 @@ class TestMsgResetDeviceSkipbackup:
                 strength=self.strength,
                 passphrase_protection=False,
                 pin_protection=False,
-                language="english",
+                language="en-US",
                 label="test",
                 skip_backup=True,
             )
diff --git a/tests/device_tests/test_msg_resetdevice_bip39_t2.py b/tests/device_tests/test_msg_resetdevice_bip39_t2.py
index 11371fb617..f44853de8f 100644
--- a/tests/device_tests/test_msg_resetdevice_bip39_t2.py
+++ b/tests/device_tests/test_msg_resetdevice_bip39_t2.py
@@ -87,7 +87,7 @@ class TestMsgResetDeviceT2:
                 passphrase_protection=False,
                 pin_protection=False,
                 label="test",
-                language="english",
+                language="en-US",
             )
 
         # generate mnemonic locally
@@ -189,7 +189,7 @@ class TestMsgResetDeviceT2:
                 passphrase_protection=True,
                 pin_protection=True,
                 label="test",
-                language="english",
+                language="en-US",
             )
 
         # generate mnemonic locally
@@ -235,4 +235,4 @@ class TestMsgResetDeviceT2:
     @pytest.mark.setup_client(mnemonic=MNEMONIC12)
     def test_already_initialized(self, client):
         with pytest.raises(Exception):
-            device.reset(client, False, 128, True, True, "label", "english")
+            device.reset(client, False, 128, True, True, "label", "en-US")
diff --git a/tests/device_tests/test_msg_resetdevice_slip39_advanced.py b/tests/device_tests/test_msg_resetdevice_slip39_advanced.py
index f8ae17bd2a..a36ab725e9 100644
--- a/tests/device_tests/test_msg_resetdevice_slip39_advanced.py
+++ b/tests/device_tests/test_msg_resetdevice_slip39_advanced.py
@@ -159,7 +159,7 @@ class TestMsgResetDeviceT2:
                 passphrase_protection=False,
                 pin_protection=False,
                 label="test",
-                language="english",
+                language="en-US",
                 backup_type=BackupType.Slip39_Advanced,
             )
 
diff --git a/tests/device_tests/test_msg_resetdevice_slip39_basic.py b/tests/device_tests/test_msg_resetdevice_slip39_basic.py
index 94f24b508b..bb018d98d2 100644
--- a/tests/device_tests/test_msg_resetdevice_slip39_basic.py
+++ b/tests/device_tests/test_msg_resetdevice_slip39_basic.py
@@ -106,7 +106,7 @@ class TestMsgResetDeviceT2:
                 passphrase_protection=False,
                 pin_protection=False,
                 label="test",
-                language="english",
+                language="en-US",
                 backup_type=BackupType.Slip39_Basic,
             )
 
diff --git a/tests/device_tests/test_msg_ripple_get_address.py b/tests/device_tests/test_msg_ripple_get_address.py
index 0cb8617a92..dd5f970772 100644
--- a/tests/device_tests/test_msg_ripple_get_address.py
+++ b/tests/device_tests/test_msg_ripple_get_address.py
@@ -31,7 +31,7 @@ CUSTOM_MNEMONIC = (
 @pytest.mark.skip_t1  # T1 support is not planned
 class TestMsgRippleGetAddress:
     def test_ripple_get_address(self, client):
-        # data from https://iancoleman.io/bip39/#english
+        # data from https://iancoleman.io/bip39/
         address = get_address(client, parse_path("m/44'/144'/0'/0/0"))
         assert address == "rNaqKtKrMSwpwZSzRckPf7S96DkimjkF4H"
         address = get_address(client, parse_path("m/44'/144'/0'/0/1"))
diff --git a/tests/device_tests/test_protection_levels.py b/tests/device_tests/test_protection_levels.py
index 9dd4946d7b..67004270f7 100644
--- a/tests/device_tests/test_protection_levels.py
+++ b/tests/device_tests/test_protection_levels.py
@@ -115,7 +115,7 @@ class TestProtectionLevels:
                 + [proto.ButtonRequest()] * 24
                 + [proto.Success(), proto.Features()]
             )
-            device.reset(client, False, 128, True, False, "label", "english")
+            device.reset(client, False, 128, True, False, "label", "en-US")
 
         with pytest.raises(TrezorFailure):
             # This must fail, because device is already initialized
@@ -127,7 +127,7 @@ class TestProtectionLevels:
                     passphrase_protection=True,
                     pin_protection=False,
                     label="label",
-                    language="english",
+                    language="en-US",
                 )
             )
 
@@ -142,7 +142,7 @@ class TestProtectionLevels:
             )
 
             device.recover(
-                client, 12, False, False, "label", "english", client.mnemonic_callback
+                client, 12, False, False, "label", "en-US", client.mnemonic_callback
             )
 
         with pytest.raises(TrezorFailure):
@@ -154,7 +154,7 @@ class TestProtectionLevels:
                     passphrase_protection=False,
                     pin_protection=False,
                     label="label",
-                    language="english",
+                    language="en-US",
                 )
             )
 
diff --git a/tests/device_tests/test_reset_recovery_bip39.py b/tests/device_tests/test_reset_recovery_bip39.py
index 2b50d8cf54..6bd7f71995 100644
--- a/tests/device_tests/test_reset_recovery_bip39.py
+++ b/tests/device_tests/test_reset_recovery_bip39.py
@@ -87,7 +87,7 @@ def reset(client, strength=128, skip_backup=False):
             passphrase_protection=False,
             pin_protection=False,
             label="test",
-            language="english",
+            language="en-US",
             backup_type=BackupType.Bip39,
         )
 
diff --git a/tests/device_tests/test_reset_recovery_slip39_advanced.py b/tests/device_tests/test_reset_recovery_slip39_advanced.py
index cdf2c745e0..eaee4e5ba0 100644
--- a/tests/device_tests/test_reset_recovery_slip39_advanced.py
+++ b/tests/device_tests/test_reset_recovery_slip39_advanced.py
@@ -176,7 +176,7 @@ def reset(client, strength=128):
             passphrase_protection=False,
             pin_protection=False,
             label="test",
-            language="english",
+            language="en-US",
             backup_type=BackupType.Slip39_Advanced,
         )
 
diff --git a/tests/device_tests/test_reset_recovery_slip39_basic.py b/tests/device_tests/test_reset_recovery_slip39_basic.py
index 9bc3151c12..43b40d4874 100644
--- a/tests/device_tests/test_reset_recovery_slip39_basic.py
+++ b/tests/device_tests/test_reset_recovery_slip39_basic.py
@@ -111,7 +111,7 @@ def reset(client, strength=128):
             passphrase_protection=False,
             pin_protection=False,
             label="test",
-            language="english",
+            language="en-US",
             backup_type=BackupType.Slip39_Basic,
         )
 
diff --git a/tests/upgrade_tests/test_firmware_upgrades.py b/tests/upgrade_tests/test_firmware_upgrades.py
index 3504a96060..ff7ede5985 100644
--- a/tests/upgrade_tests/test_firmware_upgrades.py
+++ b/tests/upgrade_tests/test_firmware_upgrades.py
@@ -36,7 +36,7 @@ MNEMONIC = " ".join(["all"] * 12)
 PATH = [H_(44), H_(0), H_(0), 0, 0]
 ADDRESS = "1JAd7XCBzGudGpJQSDSfpmJhiygtLQWaGL"
 LABEL = "test"
-LANGUAGE = "english"
+LANGUAGE = "en-US"
 STRENGTH = 128
 
 
@@ -83,7 +83,6 @@ def test_upgrade_load(gen, from_tag, to_tag):
         assert not client.features.passphrase_protection
         assert client.features.initialized
         assert client.features.label == LABEL
-        assert client.features.language == LANGUAGE
         assert btc.get_address(client, "Bitcoin", PATH) == ADDRESS
 
     with EmulatorWrapper(gen, from_tag) as emu:
@@ -102,6 +101,7 @@ def test_upgrade_load(gen, from_tag, to_tag):
     with EmulatorWrapper(gen, to_tag, storage=storage) as emu:
         assert device_id == emu.client.features.device_id
         asserts(to_tag, emu.client)
+        assert emu.client.features.language == LANGUAGE
 
 
 @for_all("legacy")
@@ -111,7 +111,6 @@ def test_upgrade_reset(gen, from_tag, to_tag):
         assert not client.features.passphrase_protection
         assert client.features.initialized
         assert client.features.label == LABEL
-        assert client.features.language == LANGUAGE
         assert not client.features.needs_backup
         assert not client.features.unfinished_backup
         assert not client.features.no_backup
@@ -134,6 +133,7 @@ def test_upgrade_reset(gen, from_tag, to_tag):
     with EmulatorWrapper(gen, to_tag, storage=storage) as emu:
         assert device_id == emu.client.features.device_id
         asserts(to_tag, emu.client)
+        assert emu.client.features.language == LANGUAGE
         assert btc.get_address(emu.client, "Bitcoin", PATH) == address
 
 
@@ -144,7 +144,6 @@ def test_upgrade_reset_skip_backup(gen, from_tag, to_tag):
         assert not client.features.passphrase_protection
         assert client.features.initialized
         assert client.features.label == LABEL
-        assert client.features.language == LANGUAGE
         assert client.features.needs_backup
         assert not client.features.unfinished_backup
         assert not client.features.no_backup
@@ -168,6 +167,7 @@ def test_upgrade_reset_skip_backup(gen, from_tag, to_tag):
     with EmulatorWrapper(gen, to_tag, storage=storage) as emu:
         assert device_id == emu.client.features.device_id
         asserts(to_tag, emu.client)
+        assert emu.client.features.language == LANGUAGE
         assert btc.get_address(emu.client, "Bitcoin", PATH) == address
 
 
@@ -178,7 +178,6 @@ def test_upgrade_reset_no_backup(gen, from_tag, to_tag):
         assert not client.features.passphrase_protection
         assert client.features.initialized
         assert client.features.label == LABEL
-        assert client.features.language == LANGUAGE
         assert not client.features.needs_backup
         assert not client.features.unfinished_backup
         assert client.features.no_backup
@@ -202,6 +201,7 @@ def test_upgrade_reset_no_backup(gen, from_tag, to_tag):
     with EmulatorWrapper(gen, to_tag, storage=storage) as emu:
         assert device_id == emu.client.features.device_id
         asserts(to_tag, emu.client)
+        assert emu.client.features.language == LANGUAGE
         assert btc.get_address(emu.client, "Bitcoin", PATH) == address
 
 
diff --git a/vendor/fido2-tests b/vendor/fido2-tests
index 67f0023be4..f81bb68dab 160000
--- a/vendor/fido2-tests
+++ b/vendor/fido2-tests
@@ -1 +1 @@
-Subproject commit 67f0023be4913a86f62bedf700f86ca3079cf842
+Subproject commit f81bb68dabf90d76ebe57e665363370bf56b77f9