Mozilla offers two official places to ask a support question: a forum and live chat. The Mozilla community offers many places to get third-party support.
In the forum, your question will be posted in public, which allows the community to participate in helping you with your problem. Don't forget to search the forum for previously asked questions first!
We have volunteer Firefox experts waiting on stand-by to help you with questions that simply demand a direct conversation. Now you can chat with knowledgeable Firefox community members who troubleshoot via our live chat site.
Note that our live chat service isn't open 24/7. If it is closed, you are better off asking your question in the forum instead.
In addition to the two main places to ask for help above, there are other ways of getting help. Please see our Autre support pour le navigateur Firefox.