Why doesn't my icon work?

[Aquede]

The python ICONS in the left sidebar are different from those in the right sidebar

[jkazimierczak]

I have the same issue for months now, but never bothered to checkout why. This might be related to the issue, that the IDE display default font - no matter whether it's New UI or Classic UI.

I'm not a maintainer, but an issue is there: #465