GoMeet is essentially the URL associated with virtual meetings created using the Online Meeting software application.
To answer your question, yes, Firefox can be used to operate GoMeet.
While Chrome 49 and the new Edge browser are "recommended," this online meeting solution offers a desktop application for hosting (or attending) a meeting for those using Firefox, Safari and older versions of Edge web browsers.
GoMeet is essentially the URL associated with virtual meetings created using the Online Meeting software application. Online Meeting is the remote meeting software component of the CommCare cloud communications bundle, Elevate is the CommCare companion application of Online Meeting and is used for cloud-based voice communication/telephony (among other things).
Any browser, including Firefox, can be used to play back recorded videos of meetings created using the Online Meeting software application.