The most famous forms of Holocaust denial and revisionism tend to focus on Jews, casting doubt, for example, on how many were exterminated in the camps. But denying the impact the Nazis had on the other groups they targeted, including queer and trans people, disabled people and Romani people, is still Holocaust denial. Maybe someone should tell J.K. Rowling.
Trade unions and lgbt clubs were attacked within the first three months after Hitler became the Chancellor. Already in the first month trade union offices and lgbt clubs were destroyed by the SA and people were sent to camps.