Issue Summary

In a scenario when there are multiple users already added to a multi-user picker field, all values except one get removed when the same field is also on a transition screen and any required field (by validator) is not being filled. After trying to run the transition, the expected error is displayed ("Field XXX is required"), but values are removed from a custom multi-user picker field and only one value remains.

Steps to Reproduce

1. Create a custom field of type Multi user-picker
2. Add several users as a default value for that field
3. Create a transition screen which contains the multi user-picker and some additional fields
4. Make those additional fields required by using a validator in the workflow
5. Run the transition which uses the transition screen
6. Don't provide the values for the required fields and try to run the transition

Expected Results

An error message should be displayed, saying that "field XXX is required" without making any changes to existing fields

Actual Results

The error message is displayed as expected but removes values in the multi user-picker field, leaving only one user

Workaround

Enable the "new transition experience" in the personal settings