Lightroom / no GPU acceleration in the before-view

Hello,

I noticed that the GPU acceleration is obviously not used in the "Before View". This leads temporarily to sometimes clearly noticeable delays and a high CPU load, especially when developing raw files during the before/after switch. Switching to the before view causes such a high CPU load on my computer (iMac Pro 2017, OS Big Sur, 32GB Ram, 3.2 GHz 8-core Intel Xeon W, Radeon Pro Vega 56 8 GB) for some raw images that the whole system is slowed down and I have to wait several seconds again and again. I think I can safely say that it is related to the fact that the GPU is not used in the before view and therefore the CPU has to do all the work here alone.

You can test it very easily. It's best to open a raw file in the Develop module (can also be completely unprocessed), use the magnifying glass to enlarge the image view a bit so you can move the image with the mouse, and then randomly move the image back and forth for a few seconds as fast as possible. In the normal/current view, the CPU load should increase just a bit and especially the GPU load should increase. You then do the same in the before view (shift-v), here the CPU load should increase significantly and the GPU load should stay around 0%. Depending on how fast/slow your computer is, you'll probably notice the difference right away, because the image in the before view will immediately start to jerk when scrolling fast.

I would be interested to know if any other Win/Mac users can confirm the problem and in particular if both operating systems and also the newer M1 Macs are affected by the problem and if this is possibly a bug?

Lightroom Classic 11.0.1
MacOS Big Sur, iMac Pro 2017,  32GB Ram, 3.2 GHz 8-core Intel Xeon W, Radeon Pro Vega 56 8 GB