When separator expands items on right dissappear

xfce4-panel 4.16.4

I was using a separator to keep some items on the right side of the panel but after the last update it stopped working as expected.

This is without the separator expanded

This is when I expand the separator. You can see the separator is on the far right, but all the other icons disappear

I have a two monitor setup

• 1st monitor: 27' at 3840x2160 (4K)
• 2nd monitor: 22' at 1920x1080 and scale: 1.5x

Also I have window scaling: 2x