There are a couple of toolbar icons whose direction depend on the content direction rather than the interface. For instance, the list icons (bullet list, number list, etc) depends strictly on the content of the document (and specifically the context that the cursor's in, in case the document contains multiple directionalities) and not the UI language.
Specifically, the toolbar has two sets of classes that are applied to it depending on the context of the cursor: ve-ui-dir-inline-rtl/ltr and ve-ui-dir-block-rtl/ltr
We used to have the icons specified in a VE-specific css file that defined the directions of those icons based on the above classes rather than the overall UI directionality. The classes seem to still be properly applied, but the icons are no longer defined to "listen" to this rule.
Lists (bullet/number) icons should go by the direction of the ve-ui-dir-block-(ltr/rtl) class and completely ignore the UI direction.
This used to work, and is now broken.