uBlock rule not blocking ws-eu.pusher.com requests from Qobuz web client despite being enabled

[optimusprimespace]

Prerequisites

• This is NOT a YouTube, Facebook, Twitch or a shortener/hosting site report. These sites MUST be reported by clicking their respective links.
• I read and understand the policy about what is a valid filter issue.
• I verified that this issue is not a duplicate. (Use this button to find out.). Comment in the old issue threads even when they are closed or even if you have a different problem.
• I did not remove any of the default filter lists, or I have verified that the issue was not caused by removing any of the default lists.
• I did not enable additional filter lists, or I have verified that the issue still occurs without enabling additional filter lists.
• I do not have custom filters/rules, or I have verified that the issue still occurs without custom filters/rules.
• I have verified that the web browser's built-in content blocker/tracking protection, network wide/DNS blocking, or my VPN is not causing the issue.
• I have turned off all other extensions and the issue still persists. (exception "Firefox Multi-Account Containers").
• If this is about a breakage or detection, I have verified that it is caused by uBlock Origin and isn't a site or browser issue.
• I did not answer truthfully to ALL the above checkboxes.

URL(s) where the issue occurs.

https://play.qobuz.com

Description

I've been experiencing a persistent issue with the Qobuz web client in Librewolf, where it makes requests to ws-eu.pusher.com every minute or so. This issue has been ongoing for a long time, and I've noticed it across various versions of Librewolf and uBlock. Currently, I'm running Librewolf version 135.0-1 with the latest uBlock version (1.62.0). Despite using uBlock to block the request within the browser, it still manages to get through and is caught by my Pi-hole. I've taken screenshots of uBlock and Pi-hole to illustrate the issue. I'd appreciate it if someone could investigate this problem and help me understand why the block is not being effective, as it seems to be bypassing uBlock's blocking functionality.

Other extensions used

Violentmonkey

Screenshot(s)

Screenshot(s)

Qobuz:

uBO

Configuration

Details

uBlock Origin: 1.62.0
Firefox: 135
filterset (summary):
 network: 143688
 cosmetic: 41470
 scriptlet: 21799
 html: 2243
listset (total-discarded, last-updated):
 default:
  user-filters: 0-0, never
  ublock-filters: 40460-117, 36m Δ
  ublock-badware: 11924-6, 36m Δ
  ublock-privacy: 2218-33, 36m Δ
  ublock-unbreak: 2614-1, 36m Δ
  ublock-quick-fixes: 218-15, 36m Δ
  easylist: 68690-225, 36m Δ
  adguard-spyware-url: 1969-138, 2d.18h.3m
  easyprivacy: 53334-45, 36m Δ
  urlhaus-1: 21790-0, 15h.58m
  curben-phishing: 1608-0, 15h.58m
  plowe-0: 3543-991, 11d.16h.9m
  LegitimateURLShortener: 2714-171, 36m
filterset (user): [empty]
hostRuleset:
 added: [array of 10 redacted]
userSettings:
 advancedUserEnabled: true
hiddenSettings: [none]
supportStats:
 allReadyAfter: 167 ms (selfie)
 maxAssetCacheWait: 63 ms
 cacheBackend: indexedDB
popupPanel:
 blocked: 141
 network:
  braze.eu: 8
  googletagmanager.com: 1
  pusher.com: 119
  sentry.io: 12
  surveysparrow.com: 1

[stephenhawk8054]

It could be that the site is making those domains to be prefetched by DNS first: uBlockOrigin/uBlock-issues#2913

If you want to check whether the connections are blocked or not, use browser's network devtools.

[optimusprimespace]

Pressing F12 and going into the network, it seems like it says that uBlock did in fact block the request. I still don't know if it's safe to ignore these requests that are appearing in Pi-hole.

[stephenhawk8054]

Yes, that means the connections never reach the destination server. They could be just being prefetched by the browsers at DNS.

You can try to access about:config and switch these values to false and test again:

network.early-hints.enabled
network.early-hints.preconnect.enabled
network.preconnect

If they don't work, it's better to ask at Firefox' support community.

[optimusprimespace]

The about:config settings don't work but thanks for trying to help me this quickly. Very much appreciated. I still don't know where to ask exactly the Firefox team...