For bugs in Firefox Desktop, the Mozilla Foundation's web browser. For Firefox user interface issues in menus, developer tools, bookmarks, location bar, and preferences. Many Firefox bugs will either be filed here or in the Core product. (more info)
When using --screenshot flag it usually doesn't make sense to use the default profile since it will likely be in use. Instead we should default to a temporary profile unless a profile is explicitly chosen with the --profile or -P option.