A new privacy preference for accessibility has been added to ‘Privacy & Security’ section of Reorganized settings in Firefox 57, which, when enabled, prevents Accessibility services from accessing the browser. Mozilla has added this option to provide users more control over the accessibility access.

“We’re detecting a long list of obscure and some not so obscure 3rd party Windows applications that use accessibility to snoop on user activity. We want to cut down on this by better communicating when a11y is active “.

” This bug is about adding a new section under preferences -> privacy that displays a11y active state and provides a switch to force accessibility off.”

Firefox 57 offers a preference to prevent Accessibility tools from accessing the browser

Firefox New Preferences Landed in Nightly

Similar to Private browsing indicator, Firefox shows a visual indicator in the tab bar when accessibility is active. User can able to click on the accessibility indicator and navigate to help page, which tells what happens when you allow or restrict access to accessibility services.

FYI, the Accessibility section in the about:support page  displays information about accessibility status -activated/deactivated and Process name of the Accessibility Instantiator (Accessibility app) name) that ran from Windows.

At the moment, the bug not yet fixed and the issue of Accessibility Instantiator field is blank on about:support page when Screen Reader is active, needs to be resolved as well.

Force-disable Accessibility in Firefox 57

When the user checks ‘Prevent accessibility services from accessing your browser option’ in Settings, Accessibility will be force-disabled