Relation fields: can the values in the pop-up be sorted?

When the uses clicks on a relation field, a pop-up shows existing values that the related table holds. There is a quick search bar, which works very nice. It looks like the pop-up has some sort of memory, as it first shows values that have been used or clicked recently. For the rest, I cannot see the logic to the sorting of the values.

My client asked if it is possibe to show a sorted list of values. Especially when there are only 10 or 20 values, sorting is a logical and practical way to show the values the user can select from.

Anyone knows a) what the current sorting algorithm is, and b) if we can change the way the values are sorted?