Version 3.5.0.11614 Alpha: "Mute voice" button size in mixer sometimes incorrect

Hi,
I've noticed sometimes (seen it 2 or 3 times now), that 3 of the 4 mixer mute voice buttons end up being incorrect, see attached screenshot.
The mixer ends up being much too wide as a result.
The action that (probably) led to this was loading a new soundfont into the Synthesizer.
Regards,
Matt.