Spectrogram options reset when reshaping verification grid

[hudson-newey]

Steps

1. Create a verification grid that fits on the screen (> 1)
2. Change an option on the last grid tile spectrogram (e.g. colour)
3. Shrink your browser window until it doesn't fit on the page anymore
4. Maximise your browser so that you can see the last grid tile again
5. You will see that the spectrogram options have been reset to the default

I expect that if I change a spectrograms option, it will not be reset to the default until I make a full page of decisions.

This is especially annoying when moving the browser window around because moving the browser window between monitors because dragging the browser will cause it to window and then maximise