Requests to `www.recaptcha.net` broken even is site is unblocked.

[nitz]

Brief

When attempting to use pages that make use of ReCaptcha via the www.recaptcha.net URL, Disconnect seems to be breaking those requests. It appears that it modifies the request in the area after the address that usually specifies the HTTP version (e.g.: HTTP/2); instead replacing it with undefined. This causes the request to fail with NS_ERROR_DOM_BAD_URI.

"Unblock Site" doesn't change the behavior. Disabling the extension completely, however, does.

Reproduction Steps

I've reproduced the issue in a fresh install of Firefox 128.0.2, running in a Windows 10 19041.4651 Sandbox.

Starting from a fresh sandbox:

1. Download (here), install Firefox & finish it's setup.
2. Install the Disconnect extension from the firefox addon site.
3. Open the developer tools, and switch to the "Network" tab.
4. Tick the checkbox for "Disable Cache" in the upper right of the tool window.
5. Navigate to the url: https://www.moxfield.com/account/signin
6. Observe that the GET request made to www.recaptcha.net fails with the error NS_ERROR_DOM_BAD_URI.
7. In a second tab, navigate to about:addons.
8. Disable or remove the Disconnect addon.
9. Back in the first tab, refresh the page.
10. Observe that the GET request to www.recaptcha.net succeeds.

Expected Behavior

Ideally, the extension shouldn't cause requests to www.recaptcha.net to fail even if the origin site is blocked. At the very least, when the origin site is unblocked, those requests shouldn't be modified. Disabling the extension as the only recourse is intuitive to say the least. (I spent more than a few hours figuring out it was Disconnect causing this in the first place 😂)

Thanks for taking a look, and for the fantastic extension!

[PlyingFigeon]

Just wanted to chime in and say I've been encountering the same issue. Unblocking the site or unblocking specific requests within the extension menu doesn't work either. Disabling the extension has been the only solution.

[martbean]

Same here with recaptcha and also hcaptcha (www.hcaptcha.com). Thanks nitz for figuring out that disabling Disconnect is a workaround. Hopefully it can be fixed as I don't want to stop using Disconnect.

[asdasd1dsadsa]

I have same issue while accessing zotero.org. I got source URI is not allowed in this document in console for the recaptcha script embedding. Click unblock site does not fix but disable this extension in firefox works.

[sentisso]

Issue still persists for me as of today (e.g. site https://floorplanner.com/ where recaptcha.net is getting blocked).

However, disabling the Disconnect extension wasn't necessary as:

1. unblocking the site
2. restarting the browser

worked (although only refreshing the site without restart didn't work).

I'm running on Arch Linux, Firefox Developer Edition 145.0b9

[rnotlnglgq]

I could still confirm this issue, ranging from 2024 to 2025. And it seems that the newer versions of this extension are not open source in this repository, so we cannot fork and fix it.