When replying to a question it's often useful to copy the $\LaTeX$ source of formulas in it by pressing the edit button and cp&p from the source text. (And eventually modify them in the answer.)
Sometimes these formulas appear in comments, but editing them, thus also copying the formulas from them is only possible above the reputation of 2000.
My feature request is that (while keeping editing restricted to high reputation members) copying from the source was enabled for everybody.