Fill in the blanks - 2 correct answers result in wrong answer even though correct

Moodle 3.6.9, desktop, Chrome

Fill in the blanks 1.11.4

When creating a fill in the blanks content type and giving two correct answers seperated by / - i.e. is/was only the 2nd answer i.e was will visually count as the correct answer. It will still give the correct grade but visually it will be marked as wrong.

Below is an example of both var / har været being a correct answer. When the studentgivs var (the first option as the answer it is marked with red as being wrong.

If the student gives the 2nd option - har været - as the correct answer it is marked with green as correct.

In both cases the grade is correctly given as 10/10 but it is very confusing behaviour.