This is in now. #2787 first added friends with a closed DM to the forward picker, and #2790 then reworked the whole forward modal. You can search for any friend by name, whether or not you have a DM open with them, and forwarding to them opens the DM automatically.
With an empty search, the list shows the places you've recently visited and forward to most often. Friends you haven't talked to in a while show up as soon as you start typing their name.
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Comment by Hampus