Firefox 57 : How to disable Accessibility Services

Do you’ve fears of any third-party accessibility service or tool is snooping on your browsing activity in Firefox browser? You don’t have to, as Firefox from version 57 onwards, shows a visual indicator in the toolbar when accessibility is enabled and allows to disable accessibility applications access to Firefox browser through a preference in Privacy & Security Settings.

• Firefox 57 lets you Prevent Accessibility tools from accessing the browser

How to disable Accessibility Services in Firefox 57

Clicking on the Accessibility Services indicator takes you to a help page about accessibility services in Firefox browser.

If you suspect anything wrong, head over to about:support page and scroll down and look for the value of Accessibility Instantiator  under ‘Accessibility Section’.

FYI, Firefox retrieves and displays the information about accessibility application in that entry.

For e.g if NVDA screen reader is accessing Firefox, then it’s value will be shown in the Accessibility Instantiator entry as ‘NVDA, UIAUTOMATION|’

Firefox shows some encoded values for known accessibility applications in the Accessibility Instantiator entry, which you can find below.

If the application is trustworthy and you’re using intentionally, continue to use it. If not, uninstall that application, if that’s not possible, disable accessibility services in Firefox browser, here is how that can be done.

1. Click on hamburger menu, select Options
2. Select ‘Privacy and security’ and under ‘Permissions’,  check ‘ Prevent accessibility services from accessing your browser’.
3. Restart the Firefox browser.

After restart, if you visit about:support page and check Accessibility section, you can notice ‘Accessibility Activated’ value as ‘false’ and ‘Prevent Accessibility’ will be set to ‘1’.