hi and welcome to the forum.
A warm stall is a common failure mode on older Focii and a frequent topic of discussion here. The usual suspects are a cracked PCV hose or a dirty/failed IAC valve. Plug those terms into the forum search box and you'll find alot of useful info.
Neither component is in plain view, but the PCV hose is the easier one to diagnose first in your process of elimination. I pulled the airbox and intake runner off while replacing the driver's side motor mount, which allowed easy access to the hose for inspection.
"I'm jealous of girls because they get to wear dresses." (Todd Flanders)