HassConnect Suspend/Resume Issue

[Scoff123]

Describe the bug
The suspend/resume connection logic fails to reconnect after the browser tab/window has been hidden for more than 5 minutes. The visibilitychange event to visible does not always fire when returning to the page, causing the resume logic (onVisibleOrResume()) to never trigger. The connection attempts to reconnect but fails repeatedly with error code 3, leaving the dashboard stuck showing "Connection lost. Reconnecting..." indefinitely.

To Reproduce
Steps to reproduce the behavior:

1. Load a hakit React dashboard in a browser (tested with both direct panel URL and ingress URL)
2. Enable debug logging in HassConnect:

   <HassConnect
     hassUrl="http://homeassistant.local:8123"
     options={{
       handleResumeOptions: {
         debug: true,
         onStatusChange(status) {
           console.log("[HassConnect] Connection status changed:", status, new Date().toISOString());
         },
       },
     }}
   >

3. Wait for connection to establish (see [HassConnect] Connection status changed: connected in console)
4. Either:
   • Switch to a different browser tab, OR
   • Minimize the browser window to taskbar
5. Wait 6-8 minutes (longer than the default 5 minute hiddenDelayMs)
6. Return to the dashboard tab/window
7. Observe "Connection lost. Reconnecting..." message that never resolves

Expected behavior
When returning to the page:

1. visibilitychange → VISIBLE event should fire
2. onVisibleOrResume() should trigger
3. pendingResolve() should be called to lift suspension
4. Connection should successfully reconnect

Screenshots / code examples

Successful reconnection (visibilitychange fired correctly)

[HassConnect] Connection status changed: pending 2026-02-06T12:07:44.323Z
[SR] Connection is already active → handleSuspendResume will manage suspension
[HassConnect] Connection status changed: connected 2026-02-06T12:07:44.335Z
[SR] handleSuspendResume() initialized; debugging is ON

[SR] visibilitychange → HIDDEN
[SR] onHidden() triggered
[SR] Calling connection.suspendReconnectUntil(...)
[HassConnect] Connection status changed: pending-suspension 2026-02-06T12:08:07.609Z
[SR] Starting hidden delay of 300000ms before actual suspend()

[SR] Hidden timeout elapsed → calling suspend()
[SR] Connection already suspended → skipping suspend()

[SR] visibilitychange → VISIBLE
[SR] onVisibleOrResume() fired (page became visible)
[SR] Resolving pendingResolve() on actual resume
[SR] pendingResolve() called → lifting suspension
[HassConnect] Connection status changed: connected 2026-02-06T12:14:30.356Z

Failed reconnection (visibilitychange never fired)

[HassConnect] Connection status changed: pending 2026-02-06T12:47:54.272Z
[SR] Connection is already active → handleSuspendResume will manage suspension
[HassConnect] Connection status changed: connected 2026-02-06T12:47:54.291Z
[SR] handleSuspendResume() initialized; debugging is ON

[SR] visibilitychange → HIDDEN
[SR] onHidden() triggered
[SR] Calling connection.suspendReconnectUntil(...)
[HassConnect] Connection status changed: pending-suspension 2026-02-06T12:48:12.815Z
[SR] Starting hidden delay of 300000ms before actual suspend()

[HassConnect] Connection status changed: pending 2026-02-06T12:56:00.673Z
subscribeUsers: failed to fetch users 3
Uncaught (in promise) 3
Uncaught (in promise) 3
Uncaught (in promise) 3
Uncaught (in promise) 3

Note: NO [SR] visibilitychange → VISIBLE event appears in the failed case.

System Info:

IDE: Visual Studio Code
Browser: Microsoft Edge Version 144.0.3719.115 (Official build) (64-bit)
npm version: 11.6.4
node version: 24.13.0
Installation method: Home Assistant OS
HA Core: 2026.1.3
Supervisor: 2026.01.1
Operating System: 16.3
Frontend: 20260107.2
@hakit/core version: 6.0.1
@hakit/components version: 6.0.1

Additional context

The dashboard is served via panel_custom which loads it in an iframe
The iframe sandbox warning appears in console: An iframe which has both allow-scripts and allow-same-origin for its sandbox attribute can escape its sandboxing.
Error code 3 in home-assistant-js-websocket typically indicates authentication/connection failure
The issue appears to be browser-dependent behavior where visibilitychange doesn't fire when the browser resumes a frozen/suspended tab

[shannonhochkins]

I will have a think about this, i know there was other users that reported something similar but I spent weeks resolving those issues and thought it was all solid!

Ill have a look and see if I can find the culprit

[Scoff123]

Great, thank you. Happy to help, so just let me know if you want me to test/check anything!

[shannonhochkins]

Will do! Can't do anything for a few days though :)