But actually you have the if statement, right before the first combobox; how it is more clean?

If you use a line() on MMCS, then you can place MMCS:MMCS out of the right margin after the first combobox making it available for the 2nd combobox. If you need to reuse it, you can define MMCS as a function MMCS(MUM), and then you can define MMCS:MMCS(MUM) after the first combobox (below or out of the printing bounds)
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