Is there a summary of keyboard shortcuts for this filter anywhere? I couldn't see any, and I got locked in "Zoom in/out" without quite knowing why/how!
Being able to resize the spectrum view, as well as being able to see the brush outline rather than just the mouse cursor would be super useful too!, as well as an option to rotate the fourier plot, because although mathematically correct it's 90 degrees out compared to the "Real world" images which makes it very confusing to use for naïve editors.
Also noticing a bug in Windows where you have to move the cursor a long way to get the brush tool to register, not useful for precision edits!
Let me know if there's a more appropriate place to file a feature request!