I wonder if single-digit non-translatables should be marked and put on the F4 list. In fact using the F4 list for a sign which takes just one tap on the keyboard is a bit rudundant and only obscures the F4 list. Of course still it does make sense for longer numbers and phrases.
That's a good point to remove single digits from the F4 list but I think marking them helps in their quick location.
Igor, would it be possible that single-digit numbers are removed from the F4 list as it used to be before fixing the latest F4 issue. That would keep the non-translatable list clearer with no detriment to the workflow.
Only one tap for a single-digit number without F4 and two taps via the list.
Still, I believe that the best way to keep non-translatable list clear is remove each element the moment it is inserted, copied or typed in the target segment and underline a currently selected non-translatable in the source segment.
Other users complained about the removal of single digits as they prefer to insert all the nontranslatables via the F4 shortcut. I guess they find it a matter of consistency in their workflow instead of using two methods to insert non-translatables.