Problem: Unexplained (and unwanted) secondary source of resizing on custom QTextEdit widget.

I have a custom AspectRatioContainer that can hold either a widget or a layout and resizes the held item to stick to a defined width:height aspect ratio — in the 2nd attachment below is a working example. In the first attachment resides my problem code. Something isn't working quite properly in the code and the held item is being resized back to its maximum possible size after the AspectRatioContainer does its work (this can be seen by the size flickering between maximum and aspect-ratioed when resizing). The goal is to find this source of resizing and remove it if possible. Any help is much appreciated!