Problem with duplicate set of first element of array of strings

[AlexandrFugin]

In version 8.7.1, I found a problem. I print an array of strings, and I observe the following behavior: the first element of the array is displayed, then it disappears and the second element should be output, but the first element of the array is output again. After that everything works normally.
I rolled back the version of the type to 8.5.2 - in this version there is no such problem.
Please tell me how to solve this problem in version 8.7.1?