I think we're going to need to see the file - I can't determine if you're working on a font symbol or something else. However, it's my understanding that you can, in the current versions of Inkscape, do a group of a sole (one) object, just select it and choose group. That might be why they dropped the convert to group command. So give that a try, and if it doesn't work, perhaps attach a file or what the symbol is.