Dashboard panel URL error message contains technical details

[frenck]

Checklist

• I have updated to the latest available Home Assistant version.
• I have cleared the cache of my browser.
• I have tried a different browser to see if it is related to my browser.
• I have tried reproducing the issue in safe mode to rule out problems with unsupported custom resources.

Describe the issue you are experiencing

When creating a new dashboard, and something goes shout:

We shouldn't have such error message. The technical details there are not user-friendly.

Ideally the error message should have been shown on the field that is problematic as wel..

Describe the behavior you expected

User-friendly message

Steps to reproduce the issue

1. Create a new dashboard
2. Use an dashboard URL/path that is already in use
3. Be amazed.
   ...

What version of Home Assistant Core has the issue?

2025.10.0b0

What was the last working version of Home Assistant Core?

unknown

In which browser are you experiencing the issue?

Unrelated

Which operating system are you using to run this browser?

Unrelated

State of relevant entities

Problem-relevant frontend configuration

JavaScript errors shown in your browser console/inspector

Additional information

No response

[timmo001]

Appears to come from the core side

frontend/src/panels/config/lovelace/dashboards/dialog-lovelace-dashboard-detail.ts

Line 286 in facce7b

this._error = { base: err?.message || "Unknown error" };

frontend/src/panels/config/lovelace/dashboards/ha-config-lovelace-dashboards.ts

Lines 450 to 452 in facce7b

	createDashboard: async (values: LovelaceDashboardCreateParams) => {
	const created = await createDashboard(this.hass!, values);
	this._dashboards = this._dashboards!.concat(created).sort(

frontend/src/data/lovelace/dashboard.ts

Lines 49 to 53 in facce7b

	hass.callWS<LovelaceDashboard>({
	type: "lovelace/dashboards/create",
	...values,
	});

Core:

https://github.com/home-assistant/core/blob/aacff4db5d92b5c61dfdc3261cab96ae6dba40ff/homeassistant/components/lovelace/dashboard.py#L289-L291

Appears to be added by the vol.humanize.humanize_error(msg, err) function:

https://github.com/home-assistant/core/blob/aacff4db5d92b5c61dfdc3261cab96ae6dba40ff/homeassistant/components/websocket_api/connection.py#L282-L283