Feature request: resize from a corner not centre

[asteele4]

When watching 4K movies on my Macbook Pro I will reduce their size with Command-zero so I can be doing other work at the same time.

What's annoying is that it reduces all sides so it's in the centre of the full size display. Can you provide an option so the resizing only moves two sides rather than 4.

Example:

Current behaviour:

1. Open a high res video.
2. Ensure top left corner of the video window is in the top left corner of the display.
3. Press Command-zero to halve the size of the video.
4. The window is now in the centre of the previous window space

Desired behaviour:

Same as above but after pressing Command-zero the window is now half the size but remains in the top left corner of the display.

Obviously, my preference is anchoring it to the top left corner, but I imagine such a feature would be more generally implemented: resize using all 4 sides (current method), only move the right and edges (my preference), only move left and top edge, etc.

I've tried to achieve this via Preferences -> UI -> Window -> Initial Window position, but that only seems to apply to the initial window position, not the position after resizing. If this option also applied after resizing that would be another way to implement this.