Dock: pixel gap when using fractional scaling

[lyfja]

I use 125% scaling and I noticed a small pixel gap next to the dock. It appears no matter at which position I place the dock (but may only be visible next to a maximized window) and it happens consistently.

From my testing, the gap only appears at 75%, 125% and 175% scaling.

125% scaling (gap at the bottom of the screen):

100% scaling:

Sometimes I notice the same happening to the panel (which makes sense since AFAIK they're the same thing under the hood) but I can't replicate the issue consistently with the panel for some reason.

[git-f0x]

I wonder if this is related to the 1 pixel line that prevents interaction on the bottom and right screen edges (which is a bug), since I can also reproduce this on the right screen edge (with both the dock and panel), but not on the top and left edges.