Interesting thing I found on Wikipedia:
https://en.wikipedia.org/wiki/Antifaschistische_AktionUnder the leadership of Ernst Thälmann, the KPD had become a staunchly Stalinist party, and it had been largely controlled and funded by the Soviet leadership since 1928; the party had adopted the position that it was "the only anti-fascist party" while it regarded all other parties, and especially the Social Democratic Party (SPD), as "fascists." The KPD did not view "fascism" as a specific political movement, but primarily as the final stage of capitalism, and "anti-fascism" was therefore synonymous with anti-capitalism. The KPD stated that "fighting fascism means fighting the SPD just as much as it means fighting Hitler and the parties of Brüning."
A bit I found interesting