It says it wasn't a "formal alliance". The Nazi-Soviet pact was alliance for practical purposes as seen with joint "victory parades" with the Wehrmacht and Red Army and expanded trading.
> was alliance for practical purposes as seen with joint "victory parades"
Alliance would mean joint fighting, not joint parading. Yes they secretly divided Europe on a map, and agreed not to fight over it, that not an alliance.
> I'm not sure what specific "rebutted by historians" you're talking about
Your second link on the French communist party activities during 39-41. It's like you didn't even read what you linked as source:
> but later historians have downplayed the PCF's role in any such actions, stating that they were isolated cases
I'm not sure what specific "rebutted by historians" you're talking about. There were disclosures about Nazi-Soviet secret protocols in 1946 : https://en.wikipedia.org/wiki/Molotov%E2%80%93Ribbentrop_Pac... though Soviet attempts to deny this were not credible: https://en.wikipedia.org/wiki/Molotov%E2%80%93Ribbentrop_Pac...