Do you know how dangerous new vs old flux is? I'm using some old Канифоль from the USSR and get headaches while soldering. Fume extraction would probably be a good idea, but I solder no more than 4h a year
There is a technique where you breathe out as you solder. No idea if канифоль is toxic or not but honestly if it gives you headaches why not try another type? Or wear a respirator?
I use Канифоль/rosin flux as well and use a fume extractor. Rosin flux is the most common for flux-cored solder in my experience.
But a few times a year is unlikely to be an issue, soldering health effects are in people who do it for work.