CVE’s

Under certain circumstances, a JavaScript alert (or prompt) could have been shown while another website was displayed underneath it. This could have been abused to trick the user.
*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 97.

Web-accessible extension pages (pages with a moz-extension:// scheme) were not correctly enforcing the frame-ancestors directive when it was used in the Web Extension's Content Security Policy. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.

When importing resources using Web Workers, error messages would distinguish the difference between application/javascript responses and non-script responses. This could have been abused to learn information cross-origin. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.

The WP Edit Menu WordPress plugin before 1.5.0 does not have authorisation and CSRF in an AJAX action, which could allow unauthenticated attackers to delete arbitrary posts/pages from the blog

If a document created a sandboxed iframe without allow-scripts, and subsequently appended an element to the iframe's document that e.g. had a JavaScript event handler - the event handler would have run despite the iframe's sandbox. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.

When clicking on a tel: link, USSD codes, specified after a * character, would be included in the phone number. On certain phones, or on certain carriers, if the number was dialed this could perform actions on a user's account, similar to a cross-site request forgery attack.
*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 97.

Remote Agent, used in WebDriver, did not validate the Host or Origin headers. This could have allowed websites to connect back locally to the user's browser to control it.
*This bug only affected Firefox when WebDriver was enabled, which is not the default configuration.*. This vulnerability affects Firefox < 97.

If a user was convinced to drag and drop an image to their desktop or other folder, the resulting object could have been changed into an executable script which would have run arbitrary code after the user clicked on it. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.

By using XSL Transforms, a malicious webserver could have served a user an XSL document that would continue to execute JavaScript (within the bounds of the same-origin policy) even after the tab was closed. This vulnerability affects Firefox < 97.

If a user installed an extension of a particular type, the extension could have auto-updated itself and while doing so, bypass the prompt which grants the new version the new requested permissions. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.