2x Window Scaling breaks panel icons

I frequently switch between 1x and 2x scaling - to be able to read what's on the display from a couple meters away - and the panel icons don't seem to correctly scale up or down.

After the first scale up to 2x the icons look like this:

I've taken two screenshots: one of the left-side "start" icons, and the other of the right side tray area. The launcher icons and task bar don't seem to be affected.

Scaling back down to 1x does not help:

I found that right clicking into Panel->Preferences and then twiddling the "Row size (pixels)" fixes the icon appearance in both the 2x and 1x cases, but I would much rather this happened automatically.

This is what the 1x scaling panel should look like, for reference:

And here is the 2x panel after I twiddled the Row size property:

I am using xfce4-panel version 4.14.3 on Linux Mint 20.1