net::ERROR_FAILED for some request even in private Tab

[Daniel-at-git]

Prerequisites

• I verified that this is not a filter list issue. Report any issues with filter lists or broken website functionality by using the chat icon in the popup panel.
• This is NOT a YouTube, Facebook or Twitch report. These sites MUST be reported by clicking their respective links.
• This is not a support issue or a question. For support, questions, or help, visit /r/uBlockOrigin.
• I performed a cursory search of the issue tracker to avoid opening a duplicate issue.
• The issue is not present after disabling uBO Lite in the browser.

I tried to reproduce the issue when...

• uBO Lite is the only extension.
• using a new, unmodified browser profile.

Description

I have an issue that on some websites only(?)POST and OPTIONS method are blocked with net::ERROR_FAILED.

This issues happens also if I use a private tab where uBO lite should be disabled. Only if I disable the extension (in chrome://extensions/) the issue is gone.

I hope it's not related to #20

For
https://www.deepl.com/de/translator
it looks like this

A specific URL where the issue occurs.

https://www.deepl.com/de/translator

Steps to Reproduce

1. Open private Tab
2. go to https://www.deepl.com/de/translator
3. Open developer tools and go to network.
4. Type in "Hello" to translate in deepl
5. Wait for an error or take a look to developer tools

Expected behavior

Request(s) should not be blocked.

Actual behavior

Requests are blocked

uBO Lite version

uBlock Origin Lite 2025.1.14.952

Browser name and version

Chrome Version 133.0.6943.99 (Offizieller Build) (64-Bit)

Operating system and version

Windows 11 23H2

[stephenhawk8054]

Can you screenshot your uBOL configurations?

[Daniel-at-git]

Can you screenshot your uBOL configurations?

Here are my settings

[Daniel-at-git]

I played a litte bit with settings. If I switch to "Einfach" the issue didn't occur.

[stephenhawk8054]

Can you test again in a new browser profile with only uBOL and its default settings, then increase the mode to "Optimal"?

[Daniel-at-git]

Can you test again in a new browser profile with only uBOL and its default settings, then increase the mode to "Optimal"?

I tried it again. I started chrome with an empty profile via
"C:\Program Files\Google\Chrome\Application\chrome.exe" --user-data-dir=%USERPROFILE%\Downloads\chrome-temp

In "Einfach" everything is working (also privat tab).
If I switch it to "Optimal" the requests are blocked in a privat tab. In normal tab they are blocked after I have restarted chrome.

@stephenhawk8054 You can not reproduce the issue?

[stephenhawk8054]

I can't reproduce. The page works normally for me.

[Daniel-at-git]

I can't reproduce. The page works normally for me.

Are you using Windows 11?

[stephenhawk8054]

I'm using windows 10.

[Daniel-at-git]

I tried it again on another Systems (Windows 11 24H2 in VMWare and Linux (bare metal HW)). I could NOT reproduce the issue :-(

My windows system, with the issue, is a company notebook. GPO and Proxy is active. Chrome is installed as normal user. Maybe this is the problem? But GPO has no Policies for Chrome (under chrome://policy).

[MasterKia]

Proxy is active.

Did you try without this?

[Daniel-at-git]

Proxy is active.

Did you try without this?

Modification is blocked by GPO. Chrome use Windows Systems settings which are blocked.

But I setup squid in my network and used my Windows 11 (in VM) system to use this proxy. I could not reproduce it.

I'm sure it's not an proxy issue. If it's blocked by proxy you get not an net::ERROR_FAILED in dev tools. I also used wireshark and could not see the request to proxy. It's blocked inside windows or chrome.

[Daniel-at-git]

As I can not turn proxy off (and IMHO it will not solve my issue) I tried to get some more information via procmon.

If it's not working I get some events from the extension. Also I have some Reg-events for the interfaces.
Maybe it helps someone.....