TextEditor: inital redundant horizontal scrollbar [SOLVED]

edit:
Solved. I put the TextEditior initialization code in the //[UserPreSize] section of my GUI component first.
When I move it to the //[Constructor] section the horizontal scrollbar doesn’t appear anymore.

=== original post ===

I’ve created a multiline TextEditor. As can be seen in the screencapture on startup it displays a horizontal scrollbar that then disappears when scrolling vertically.
Why is that, or asked another way, how can I prevent it?

https://i.imgur.com/ontEGVt.gif

Upon searching the forum I found this topic:

Am I encountering a similar issue here?