If I'm not mistaken, it appears that you're using that to bypass plugins when their GUI is open. In which case, you don't need found images, as the bypass button is always in the same location relative to the front window position.
I did the same, but I felt it was worth changing to avoid the lag induced by searching for the found image.
The only drawback is that if you click away from the plugin GUI, it is no longer the front window. However, I got around this by automating it's selection as part of the bypass macro, using window titles. Still much more snappy than using found images. I only use the Tracks and Mixer windows in my main screenset, so this works fine for me. However, if you habitually change screensets, you could easily create a window name whitelist that includes all your main Logic windows; any other window whose name does not appear on the whitelist would be the plugin window. It's slightly convoluted because Logic, unlike other DAWs, doesn't title plugin windows in an identifiable way.