When there was a fire on Mir, Nasa said "Small Fire Extinguished on Mir" [1], and the actual thing was pretty severe: "The flames were large enough to span the breadth of Kvant-1, cutting off access to one of two Soyuz escape capsules", "Thick smoke rapidly enveloped the entire station, forcing all crewmembers to don oxygen masks." [2]

Given all the recent trouble Roscosmos had with the new module in addition to the engine malfunction, I wonder how bad the situation really is. What's the worst that can happen here?

[1] https://www.nasa.gov/centers/johnson/news/releases/1996_1998...

[2] https://sma.nasa.gov/docs/default-source/safety-messages/saf...