System Information
Operating system: macOS-11.5.2-x86_64-i386-64bit 64 Bits
Graphics card: Apple M1 Apple 4.1 Metal - 71.7.1

Blender Version
Broken: version: 2.93.4, branch: master, commit date: 2021-08-31 09:23, hash: rBb7205031cec4
Worked: I don't know. No version I tried worked.

Short description of error
After rendering an animation to png files, I click on Render > View Animation. On my windows machine this works as intended. But on my Macbook Air M1 the 'Blender Animation Player' window displays the rendering with wrong size and aspect ratio. It's the same with every project. Also with new ones. The rendering takes only 25% of the window and the other space is just black. The image looks also stretched (see attached screenshot)

Exact steps for others to reproduce the error
Open any project, press Render > Render Animation, press Render > View Animation