Comment by riquito
Using Firefox mobile too, it's visible. Could be one of your extensions
Using Firefox mobile too, it's visible. Could be one of your extensions
AdNauseam uses manifest version 2, too, so it will not be supported for long in Chrome / Chromium.
I've got uBO on my Android Firefox and the form is visible. UMatrix shows only first party css, no js at all, which is good. You might have other extensions. View source on my phone shows a very simple HTML page with a form that posts to list-manage.com Maybe something added to your Firefox is blocking that.
Probably Ublock Origin, which is why I use FF mobile.