No value displayed when hovering over topomap with image_interp='nearest'

I’ve noticed an inconsistency when using different interpolation methods in mne.viz.plot_topomap(). When I use image_interp=‘nearest’, there’s no value displayed at the top right corner when I hover over the topomap. This behavior is different from what I observe when using other interpolation methods.
Is this expected behavior? If so, is there a reason why the ‘nearest’ interpolation method doesn’t show the value on hover? If not, I will try to make a pull request on github.