I bought a 520i parts saw on eBay which had a red-pink-red sort of bubbly like fluid (?oil, ?detergent, ?other about the same consistency) in the oil tank. I don't know what it was, but whatever it was, the d@rned lube-impregnated sawdust that gets sucked into all parts of a saw had dried like bricks. Not even carb cleaner would dissolve it off the airfilter.
Whatever the bar lube chosen, because lube-covered sawdust gets sucked into the saw during operation, I think it might be worthwhile knowing not only (a) does it lubricate the chain (as any good oil, or soap!, will do) but more importantly (b) when it dries, e.g. when it oxidizes, does it harden like epoxy glue, e.g. do the short polymers in it "polymerize" making long polymers entangled with the wood fibers of the sawdust, resulting in an epoxy brick all around your airfilter, ignition system, cooling fins, etc.