One problem I've noticed is that certain people tend to conflate the concepts of racism and colorism (the latter also being known as shadeism).

Racism is more about people (and systems) weaponizing people's identities against them, in a way that encompasses skin tone, cultural markers, ancestry, and shared socio-political histories.

Colorism/shadeism is about the LITERAL pigment of one's skin, and how even WITHIN racial or ethnic groups, people of the same racial/ethnic background can discriminate against ONE ANOTHER due to the variations in skin pigmentation.

The history of enslavement that many Slavic people endured was inevitably accompanied by intermarriage/procreation with non-Slavic people from various parts of Africa and Eurasia. This would suggest the presence of colorism within and across the borders of Slavic nations themselves, and racism (or variations of colorism) when Slavs interact with racial/ethnic groups from outside of Eastern Europe.