While I don't know about European countries, given this is an article about America it's worth pointing out that you can, in fact, vote in the US while homeless

While I don't know about European countries, given this is an article about America it's worth pointing out that you can, in fact, vote in the US while homeless[0], using a friend/family's home, shelter, or religious center as your address. [0] https://vote.gov/guide-to-voting/unhoused https://vote.gov/guide-to-voting/unhoused