Mozilla has published one document support with a fix for the problem that is forcing Twitter not to open on Firefox.
According to one bug that Mozilla has been monitoring and working on for the past 20 days, some users may see blank pages or errors when trying to visit the social media site, and some reports also say that the problem also affects users mobile.

On devices where Firefox does not load the Twitter site, users will see the error "the site at https://twitter.com/ encountered a protocol breach" network which cannot be repaired. "
"The page you are trying to view could not be displayed because a transmission error was detected data. Contact the owners of the website to inform them about this problem. "
While Mozilla has not notified Firefox versions affected by this issue, affected users say that download errors have started appearing on both mobile and desktop devices after updating to Firefox 81.0, last month.
"There is a known temporary issue in Firefox that brings up a blank error page when loading Twitter," Mozilla explained in a support letter released earlier. "We are working hard to find a solution."
Until Mozilla engineers are able to resolve this issue, you can follow the procedure below to get rid of bugs and blank pages that appear when you try to open Twitter:
How to fix Twitter that does not load in Firefox.
1. Type about: serviceworkers in the address bar

2.Search Twitter in the list, and then click «Unregister".
3. Twitter will load normally the next time you visit it.
Reports also say that hard reloading the Twitter site using CTRL + F5 will also allow you to temporarily open Twitter pages.
In addition, the transition to: config and its deactivation dom.serviceWorkers.enabled will also remove network breach errors.