fixup! fix(core): prevent homescreen flickering on Cancel message

Author: romanz

core/src/apps/base.py

@@ -1,6 +1,5 @@
 from typing import TYPE_CHECKING
 
-import storage.cache as storage_cache
 import storage.device as storage_device
 from storage.cache_common import APP_COMMON_BUSY_DEADLINE_MS, APP_COMMON_SEED
 from trezor import TR, config, utils, wire, workflow
@@ -239,15 +238,8 @@ async def handle_GetFeatures(msg: GetFeatures) -> Features:
 
 
 async def handle_Cancel(msg: Cancel) -> Success:
-    close_others = True
-    if storage_cache.homescreen_shown is storage_cache.HOMESCREEN_ON:
-        # Homescreen is shown and only this task is running
-        if len(workflow.tasks) == 1 and next(iter(workflow.tasks)).is_running():
-            # Prevent homescreen flickering on Cancel
-            close_others = False
-
-    if close_others:
-        workflow.close_others()
+    # Prevent homescreen flickering on Cancel
+    workflow.close_others(close_default=False)
 
     raise wire.ActionCancelled
 

core/src/trezor/workflow.py

@@ -136,14 +136,14 @@ def kill_default() -> None:
         default_task.close()
 
 
-def close_others() -> None:
+def close_others(close_default: bool = True) -> None:
     """Request workflow (and UI) exclusivity: shut down all running tasks, except
     the one that is currently executing.
 
     If this is called from outside a registered workflow, it is equivalent to "close
     all tasks". In that case, the default task will be restarted afterwards.
     """
-    if default_task is not None and not default_task.is_running():
+    if close_default and default_task is not None and not default_task.is_running():
         default_task.close()
         # if no other tasks are running, start_default will run immediately
 
@@ -153,7 +153,8 @@ def close_others() -> None:
         if not task.is_running():
             task.close()
 
-    storage_cache.homescreen_shown = None
+    if close_default:
+        storage_cache.homescreen_shown = None
 
     # if tasks were running, closing the last of them will run start_default