Size of "Select List (multiple choices)" field

Hi Colleagues!
First of all I created community question:

Then I raised support ticket JSP-406481 and then [JRASERVER-67962] ( was raised.

The point is: When I create a sub-task the size of “Select List (multiple choices)” field is not well. If I edit sub-task or create a task all is ok.
Steps to reproduce are in the links mentoined above.

Here is only one question: Is there a possible workaround to avoid this? Maybe a small change in html or css?

With kind regards

Hello! Any updates here?