If you check the about:crashes page, you can use the View link to see the public-facing data from your crash report on the crash-stats server.

There is a link there to file a bug, I actually don't know if that's the right way to get data removed. There is an unrelated form to request data deletion called a "Data Subject Access Request." You can find a link to that form toward the bottom of the Privacy Policy: https://www.mozilla.org/privacy/ -- I haven't tried it myself but if you give them the URL to the crash report, they could let you know whether it's in their scope.

Thanks a lot!!! That was exactly what I was looking for but couldn't find. I will contact them.