See subject. There is explicit code that removes the "on" argument, so that it does not get disabled. Somebody must have thought something when implementing this, but I don't understand the reason.
Disabling the math-mode lfun when the cursor is inside math and the argument is on would fix bug 6709 and a couple of similar issues: Many entries in the insert_math produce nonsense (or nothing) if they are called from within math. IMHO, they should be disabled in that case. There are other menu entries for changing the type of existing formulas, so one does not need the "insert" entries for that. Georg
