Worked for me for paying my Netflix subscription.
Edit: Thanks a lot for the warning! I've disabled the 'Ignore X frame' from the extension's menu by default and would only enable it when I'm sure that I'm paying via the correct website.

You Awesome!

Excellent Job! ......... Thank you!

Suddenly today I could not get to the back end of a site at work. I refuse to use Chrome or Microsoft browsers. Thank you so much for this app, quick install and worked instantly!

A site I use for work wouldn't load but after adding this add-on it works! Thanks for solving my problem!

OK, now it works. I had "new tab override" installed pointing to Google. All worked fine until I updated to Firefox 77.0.1. Then I got the "X frame" error. I loaded Ignore X-frame-option plugin but could not make it work. Then uninstalled both new tab override and ignore X-frame-option. When receiving the developer response I realoaded both and now it works. Not being a Firefox guru, I have NO idea why but now I am very happy bunny. Many thanks.

Thanks for this great extension.

does exactly what it says

Very good, worked as advertised. Thanks. Regards. Needed this to put money into linked child's account on Microsoft/Xbox Live!

This was working flawlessly, solving my issue, until the May 3 update, at which point it stopped working. I removed the plug-in and replaced it with the prior version, and all's well.
on Firefox 68.6.1esr (64-bit)
Mac OS: Mojave 10.14.6

tried adding to github issues page
but having login problem. Essentially +1 to issue titled "Error loading some iframe"
I'm fine with prior revision, all is truly well with my use case.

Worked instantly - fast and easy! Thanks.

Do not work!

exelente herramienta para desarrolladores. Gracias 👍👍👍👍👍👍👍👍