diff --git a/core/embed/rust/src/ui/layout_bolt/ui_firmware.rs b/core/embed/rust/src/ui/layout_bolt/ui_firmware.rs
index de11a6c7c3..3199ad5276 100644
--- a/core/embed/rust/src/ui/layout_bolt/ui_firmware.rs
+++ b/core/embed/rust/src/ui/layout_bolt/ui_firmware.rs
@@ -26,7 +26,8 @@ use crate::{
             util::{ConfirmValueParams, PropsList, RecoveryType},
         },
         ui_firmware::{
-            FirmwareUI, MAX_CHECKLIST_ITEMS, MAX_GROUP_SHARE_LINES, MAX_WORD_QUIZ_ITEMS,
+            FirmwareUI, ERROR_NOT_IMPLEMENTED, MAX_CHECKLIST_ITEMS, MAX_GROUP_SHARE_LINES,
+            MAX_WORD_QUIZ_ITEMS,
         },
         ModelUI,
     },
@@ -135,7 +136,7 @@ impl FirmwareUI for UIBolt {
         _hold: bool,
         _chunkify: bool,
     ) -> Result<Gc<LayoutObj>, Error> {
-        Err::<Gc<LayoutObj>, Error>(Error::ValueError(c"confirm_value_intro not implemented"))
+        Err::<Gc<LayoutObj>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn confirm_homescreen(
@@ -574,18 +575,14 @@ impl FirmwareUI for UIBolt {
         _summary_br_name: Option<TString<'static>>,
         _cancel_text: Option<TString<'static>>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"flow_confirm_output not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn flow_confirm_set_new_pin(
         _title: TString<'static>,
         _description: TString<'static>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"flow_confirm_set_new_pin not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn flow_get_address(
@@ -603,9 +600,7 @@ impl FirmwareUI for UIBolt {
         _br_code: u16,
         _br_name: TString<'static>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"flow_get_address not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn multiple_pages_texts(
@@ -613,15 +608,11 @@ impl FirmwareUI for UIBolt {
         _verb: TString<'static>,
         _items: Gc<List>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"multiple_pages_texts not implemented",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn prompt_backup() -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"prompt_backup not implemented",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn request_bip39(
@@ -817,7 +808,7 @@ impl FirmwareUI for UIBolt {
         _value: TString<'static>,
         _verb_cancel: Option<TString<'static>>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(c"show_danger not supported"))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_error(
@@ -1039,7 +1030,7 @@ impl FirmwareUI for UIBolt {
         _text_footer: Option<TString<'static>>,
         _text_confirm: TString<'static>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(c"use show_share_words"))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_remaining_shares(pages_iterable: Obj) -> Result<impl LayoutMaybeTrace, Error> {
@@ -1161,7 +1152,7 @@ impl FirmwareUI for UIBolt {
     }
 
     fn tutorial() -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(c"tutorial not supported"))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 }
 
diff --git a/core/embed/rust/src/ui/layout_caesar/ui_firmware.rs b/core/embed/rust/src/ui/layout_caesar/ui_firmware.rs
index dc1677f389..f1b9adc75e 100644
--- a/core/embed/rust/src/ui/layout_caesar/ui_firmware.rs
+++ b/core/embed/rust/src/ui/layout_caesar/ui_firmware.rs
@@ -26,7 +26,8 @@ use crate::{
             util::{ConfirmValueParams, RecoveryType},
         },
         ui_firmware::{
-            FirmwareUI, MAX_CHECKLIST_ITEMS, MAX_GROUP_SHARE_LINES, MAX_WORD_QUIZ_ITEMS,
+            FirmwareUI, ERROR_NOT_IMPLEMENTED, MAX_CHECKLIST_ITEMS, MAX_GROUP_SHARE_LINES,
+            MAX_WORD_QUIZ_ITEMS,
         },
         ModelUI,
     },
@@ -183,7 +184,7 @@ impl FirmwareUI for UICaesar {
         _hold: bool,
         _chunkify: bool,
     ) -> Result<Gc<LayoutObj>, Error> {
-        Err::<Gc<LayoutObj>, Error>(Error::ValueError(c"confirm_value_intro not implemented"))
+        Err::<Gc<LayoutObj>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn confirm_homescreen(
@@ -222,9 +223,7 @@ impl FirmwareUI for UICaesar {
         _items: Obj,
         _verb: Option<TString<'static>>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"confirm_emphasized not implemented",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn confirm_fido(
@@ -704,18 +703,14 @@ impl FirmwareUI for UICaesar {
         _summary_br_name: Option<TString<'static>>,
         _cancel_text: Option<TString<'static>>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"flow_confirm_output not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn flow_confirm_set_new_pin(
         _title: TString<'static>,
         _description: TString<'static>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"flow_confirm_set_new_pin not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn flow_get_address(
@@ -733,9 +728,7 @@ impl FirmwareUI for UICaesar {
         _br_code: u16,
         _br_name: TString<'static>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"flow_get_address not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn multiple_pages_texts(
@@ -925,9 +918,7 @@ impl FirmwareUI for UICaesar {
     }
 
     fn set_brightness(_current_brightness: Option<u8>) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"setting brightness not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_address_details(
@@ -992,7 +983,7 @@ impl FirmwareUI for UICaesar {
         _value: TString<'static>,
         _verb_cancel: Option<TString<'static>>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(c"show_danger not supported"))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_error(
@@ -1002,7 +993,7 @@ impl FirmwareUI for UICaesar {
         _allow_cancel: bool,
         _time_ms: u32,
     ) -> Result<Gc<LayoutObj>, Error> {
-        Err::<Gc<LayoutObj>, Error>(Error::ValueError(c"show error not supported"))
+        Err::<Gc<LayoutObj>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_group_share_success(
@@ -1063,9 +1054,7 @@ impl FirmwareUI for UICaesar {
         _horizontal: bool,
         _chunkify: bool,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"show_info_with_cancel not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_lockscreen(
@@ -1155,13 +1144,11 @@ impl FirmwareUI for UICaesar {
         _text_footer: Option<TString<'static>>,
         _text_confirm: TString<'static>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(c"use show_share_words"))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_remaining_shares(_pages_iterable: Obj) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"show remaining shares not supported",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_simple(
@@ -1182,7 +1169,7 @@ impl FirmwareUI for UICaesar {
         _allow_cancel: bool,
         _time_ms: u32,
     ) -> Result<Gc<LayoutObj>, Error> {
-        Err::<Gc<LayoutObj>, Error>(Error::ValueError(c"show success not supported"))
+        Err::<Gc<LayoutObj>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_wait_text(text: TString<'static>) -> Result<impl LayoutMaybeTrace, Error> {
diff --git a/core/embed/rust/src/ui/layout_delizia/ui_firmware.rs b/core/embed/rust/src/ui/layout_delizia/ui_firmware.rs
index b0baf63e71..3310529bf2 100644
--- a/core/embed/rust/src/ui/layout_delizia/ui_firmware.rs
+++ b/core/embed/rust/src/ui/layout_delizia/ui_firmware.rs
@@ -25,7 +25,8 @@ use crate::{
             util::{PropsList, RecoveryType},
         },
         ui_firmware::{
-            FirmwareUI, MAX_CHECKLIST_ITEMS, MAX_GROUP_SHARE_LINES, MAX_WORD_QUIZ_ITEMS,
+            FirmwareUI, ERROR_NOT_IMPLEMENTED, MAX_CHECKLIST_ITEMS, MAX_GROUP_SHARE_LINES,
+            MAX_WORD_QUIZ_ITEMS,
         },
         ModelUI,
     },
@@ -81,7 +82,7 @@ impl FirmwareUI for UIDelizia {
         _chunkify: bool,
     ) -> Result<Gc<LayoutObj>, Error> {
         // confirm_value is used instead
-        Err::<Gc<LayoutObj>, Error>(Error::ValueError(c"confirm_address not implemented"))
+        Err::<Gc<LayoutObj>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn confirm_value(
@@ -347,9 +348,7 @@ impl FirmwareUI for UIDelizia {
         _hold: bool,
         _items: Obj,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"confirm_more not implemented",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn confirm_reset_device(recovery: bool) -> Result<impl LayoutMaybeTrace, Error> {
@@ -652,9 +651,7 @@ impl FirmwareUI for UIDelizia {
         _verb: TString<'static>,
         _items: Gc<List>,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"multiple_pages_texts not implemented",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn prompt_backup() -> Result<impl LayoutMaybeTrace, Error> {
@@ -780,9 +777,7 @@ impl FirmwareUI for UIDelizia {
         _path: Option<TString<'static>>,
         _xpubs: Obj,
     ) -> Result<impl LayoutMaybeTrace, Error> {
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"show_address_details not implemented",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_checklist(
@@ -1027,9 +1022,7 @@ impl FirmwareUI for UIDelizia {
 
     fn show_remaining_shares(_pages_iterable: Obj) -> Result<impl LayoutMaybeTrace, Error> {
         // Delizia: remaining shares is a part of `continue_recovery` flow
-        Err::<RootComponent<Empty, ModelUI>, Error>(Error::ValueError(
-            c"show_remaining_shares not implemented",
-        ))
+        Err::<RootComponent<Empty, ModelUI>, Error>(ERROR_NOT_IMPLEMENTED)
     }
 
     fn show_simple(
diff --git a/core/embed/rust/src/ui/ui_firmware.rs b/core/embed/rust/src/ui/ui_firmware.rs
index 112e998e4b..438aa66b01 100644
--- a/core/embed/rust/src/ui/ui_firmware.rs
+++ b/core/embed/rust/src/ui/ui_firmware.rs
@@ -15,6 +15,8 @@ pub const MAX_CHECKLIST_ITEMS: usize = 3;
 pub const MAX_WORD_QUIZ_ITEMS: usize = 3;
 pub const MAX_GROUP_SHARE_LINES: usize = 4;
 
+pub const ERROR_NOT_IMPLEMENTED: Error = Error::ValueError(c"not implemented");
+
 pub trait FirmwareUI {
     #[allow(clippy::too_many_arguments)]
     fn confirm_action(