HTTP Error 400. The size of the request headers is too long. - Azure B2C

[bolicd]

Hi,

some users are experiencing this error when using Chrome. Hellojs is working with AzureB2C and it works ok.

HTTP Error 400. The size of the request headers is too long.

This is the exception when trying to execute hello.login() which happens in chrome in some cases.

It works when we switch to incognito or use other browser.

Is this something related to the session or theres some other issue? I've tried removing cookies, clearing local storage.

[bolicd]

Deleting session, removing all cookies seems to solve this issue. It is as sometimes corrupted data is written in some of the cookies azure uses... (removing cookies from azure login screen worked)

THe issue occurs very rarely

[Mayank1728]

Hey @bolicd ! I would love to contribute however I have quite basic knowledge of Js

[MrRob0t404]

Does this issue still need to be fixed?

[luisjavcr10]

Hi, just checking in to see if this issue still needs to be addressed.

From what I’ve seen, the problem seems to be caused by the size of the request headers—specifically due to large or too many cookies being sent in Chrome. This can happen over time as session or authentication data builds up (e.g., JWT tokens stored in cookies).

The error disappears in incognito or other browsers because they don't load the existing cookie/session data.

Possible solutions:

Clear all cookies for the app domain.

Use sessionStorage instead of cookies for storing tokens if using HelloJS.

Review how authentication/session tokens are stored to avoid oversized headers.

Let me know if you'd like help testing this or if the issue is already resolved!