Android app todo-list card causing websocket overflow (4096 pending messages) on always-on tablet

[phlfr]

With the help of Claude.ai for first diagnotic and description of the problem.

The problem
When a todo-list card is displayed on an Android tablet running the Home Assistant app 24/7, the websocket connection overflows with 4096 pending messages after a few hours.

Environment

• Home Assistant Core: 2025.9.1
• Home Assistant Android app: 2025.11.4-19134
• Device: Android 13 tablet (MT11) - always on, displaying dashboard 24/7
• Entity: todo.liste_dachats (native HA shopping list)

What is expected?
The todo-list card should subscribe to updates efficiently without flooding the websocket.

What is happening?
The same todo items are sent repeatedly via websocket events:

{"id":52,"type":"event","event":{"items":[...]}}
{"id":234,"type":"event","event":{"items":[...]}}  
{"id":76,"type":"event","event":{"items":[...]}}

After a few hours: Client unable to keep up with pending messages. Reached 4096 pending messages

Workaround
Removing the todo-list card from the dashboard resolves the issue completely.

Steps to reproduce

1. Have an Android tablet with HA app running 24/7
2. Display a dashboard with a todo-list card
3. Wait 2-6 hours
4. Check logs for websocket overflow errors

Additional context

• Issue does not occur on mobile devices (app closed most of the time)
• Issue does not occur on web browser (PC)
• Only affects always-on Android tablets with todo-list cards on the continously displauyed dashboard.

the dashboard:
type: todo-list
entity: todo.liste_dachats
title: To DO

with two lines:

The errors messages:

2025-12-01 13:03:49.293 ERROR (MainThread) [homeassistant.components.websocket_api.http.connection] [140324611751456] Tablette from 192.168.1.121 (Mozilla/5.0 (Linux; Android 13; MT11 Build/TQ1A.230105.002.A1; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/142.0.7444.102 Safari/537.36 Home Assistant/2025.11.4-19134 (Android 13; MT11)): Client unable to keep up with pending messages. Reached 4096 pending messages. The system's load is too high or an integration is misbehaving; Last message was: b'{"id":52,"type":"event","event":{"items":[{"summary":"Sortir poubelle mardi soi","uid":"3918343e414e45c6a8ba36eb2eaf8707","status":"needs_action","due":null,"description":null},{"summary":"Sortir poub jaune jeudi soir","uid":"552b3ae7ea4644fd8989344c6536fe62","status":"needs_action","due":null,"description":null}]}}'
2025-12-01 13:03:56.434 ERROR (MainThread) [homeassistant.components.websocket_api.http.connection] [140324644070848] Tablette from 192.168.1.121 (Mozilla/5.0 (Linux; Android 13; MT11 Build/TQ1A.230105.002.A1; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/142.0.7444.102 Safari/537.36 Home Assistant/2025.11.4-19134 (Android 13; MT11)): Client unable to keep up with pending messages. Reached 4096 pending messages. The system's load is too high or an integration is misbehaving; Last message was: b'{"id":234,"type":"event","event":{"items":[{"summary":"Sortir poubelle mardi soi","uid":"3918343e414e45c6a8ba36eb2eaf8707","status":"needs_action","due":null,"description":null},{"summary":"Sortir poub jaune jeudi soir","uid":"552b3ae7ea4644fd8989344c6536fe62","status":"needs_action","due":null,"description":null}]}}'
2025-12-01 13:04:00.805 ERROR (MainThread) [homeassistant.components.websocket_api.http.connection] [140324532798784] Tablette from 192.168.1.121 (Mozilla/5.0 (Linux; Android 13; MT11 Build/TQ1A.230105.002.A1; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/142.0.7444.102 Safari/537.36 Home Assistant/2025.11.4-19134 (Android 13; MT11)): Client unable to keep up with pending messages. Reached 4096 pending messages. The system's load is too high or an integration is misbehaving; Last message was: b'{"id":76,"type":"event","event":{"items":[{"summary":"Sortir poubelle mardi soi","uid":"3918343e414e45c6a8ba36eb2eaf8707","status":"needs_action","due":null,"description":null},{"summary":"Sortir poub jaune jeudi soir","uid":"552b3ae7ea4644fd8989344c6536fe62","status":"needs_action","due":null,"description":null}]}}'

issued repeatedly....

I wonder whether this bug appears after a recent automatic upgrade of the Home assistant companion app.

Best regards.

[jpelgrom]

For dashboards, please check for a frontend issue: https://github.com/home-assistant/frontend/issues/.

Your Home Assistant version is relatively old, the issue may already be solved in newer versions.