Disable Firefox policies of the same origin without installing the plugin

Question

Is there a way to disable the same origin policy in Mozilla Firefox browser by switching the flag in browser ?

It is strictly for development, not for use in production.

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Note:

A similar question asked 3 years ago gave an acceptable answer that recommends users to install the plugin. I find this less secure and more cumbersome than switching a flag (for example, in about: config or passing a parameter when the browser starts like in Chrome ).

Answer 1

After you tried to find the Firefox settings for several hours, and having opened the bounty, I think the correct answer to this question is:

At the time of writing (March 2018), it is not possible to disable the same policy origin in Firefox simply by setting a flag.

I personally would recommend people use Chrome instead, because disabling this option is very easy , fast and does not require third-party software installation.

Answer 2

Instead of directly answering your question, this alternative may be viable if you also own a server

Get your server to add the following response header. (+ Apply the DevOps process or part of the code to ensure that this code is used during development)

Access-Control-Allow-Origin

.. with the value of your source domain, for example. http://example.com or alternatively * for all domains.

Answer 3

Mozilla Firefox has a boolean value that should allow the switching of the same origin policy security.fileuri.strict_origin_policy .

Go to about:config in your browser and accept the risk:

Then search for security.fileuri.strict_origin_policy and double-click it to switch it to false as follows:

I have not tested this, but, in my experience, it is a flag governing the same origin policy.

Answer 4

And back, I ran into the same problem, and for all browsers you need to add a server response header to enable CORS:

 Access-Control-Allow-Origin: * 

And for Firefox, you need to add the following additional title (for sure):

 Access-Control-Allow-Methods: POST, GET, OPTIONS 

I was not able to understand why Firefox should be different. See the blog article I wrote about this here:

https://debugnotes.wordpress.com/2015/06/17/ajax-and-ssl/