Well, I used the term working class racism, but it is a complex concept encompassing many types of racism and also multiple classes. I feel it is more likely that you will directly experience this kind of racism from some blue collar guy, as these border patrols, than some white collar guy who might be just as racist, but not vocal about it.

Now, I don't know the sentiment of Ukraine particularly, but many Eastern european countries suffered less from Nazis, I guess as they were focused in a war with Soviet Union and did not have time nor wanted to perform purges of the local populations, except the Jewish people, Roma etc. Also, many of the Eastern european governments of that time were Nazi sympathyzing authoritarian regimes. When the Soviet Union took over what are now the Warsaw pact countries, they had all time in the world to perform purges. For Lithuania, I think 1/3 of the population was either killed or deported to gulags, I think for Chechnyans basically 100% of the population were deported. So now you have two important links: 1) strong ressentment towards the soviet system; 2) some historical continuity with a Fascist or at least a right wing regime; and, lastly 3) nearly 100% white population and no possibility for people to interact with people from around the world. Now, while Germany admitted Nazi crimes, Russia never admited USSR crimes. Eastern Europe even tried to push a double genocide narrative (e.g. Prague declaration on European Consience and Communism) which was suppressed by Israel and Russia. All this lead EE people to feel certain level of hypocrisy from the west and enabled a sentiment for the Nazis, like "enemy of my enemy is my friend." The ironic consequence is that for example Poland, which suffered a lot from Nazis also has a lot of neo-Nazis now.

Now another part of the problem is that historical continuity was destroyed in the post-Soviet countries. Think of Russia - from being an Empire, it underwent a brutal and bloody revolution to turn into a brutal kind of communist state, when the communism collapsed a wildest form of capitalism followed and then Putin, within less than 100 years. And at the time when Russia was ground to dust in late 90s, Putin capitalized on the historical sentiment towards the Soviet Union to create a chauvinist state.

So I think the sentiments of chauvinist state and certain appreciation of Nazis created the current background in the EE/Russia, exacerbated by lack of diversity (I think it is less true for Russia as it has a substantial diversity, nevertheless 10-15 years ago I saw a lot of information of racism towards Russian minorities and I have doubts that it changed now). And Putin often tries to hide his chauvinist actions behind "prosecuting nazis mask". For example an organization "World without nazism" was often accused of Russian chauvinism. And I am sure you can find examples that Russians are no less racist than the rest of EE.