Just wondering - is it possible to somehow track two specific flights simultaneously? For instance, say I wanted to watch Old Crow Airlines flight 1234 (OC1234) DFW-ORD , and Park Pigeon Airlines flight 4321, IAH-ORD, at the same time. Is there a way I can do this on one map without having to switch back and forth?
Oh, pardon me. I had a completely different idea from reading that title! 
hehehehehehehehehe
…try to ask a serious question, and sure enough, the dirty little minds seep out of the slime.
Don’t worry, you’ll get a serious answer. I just couldn’t resist the opportunity. 
It was a big fat softball, and nobody else had swung at it yet.
I’m pretty sure there’s no way to get two selected flights on the same map, but I’ll wait for the staff to pipe up with the right answer. I know you get multiple AC on a map when you ask about an airport instead of a flight number; for example you see several dozen AC around ORD. But I’ve never seen a way to query two flights and get one page with a common map.
If you have a compelling reason you want this feature, maybe they’ll agree that everyone will benefit, and they’ll add it to the list of future work. They’ve been rolling out a ton of beautiful new features just in the last 2 weeks. 
Yes, I’ve seen the new features, and they’re fine, for “pretty” - but I need something that’s more functional (for me, anyway!) I’m a line mechanic, and I have two, and sometimes three, inbound flights nightly that I’d like to be able to track. Maybe it’s just me, but it seems like this would be a useful function.
Seriously, when I need to do that, I just open up multiple tabs in my browswer and make them all on the screen simultaneously.
You want serious? Contact the FA staff directly rather than asking your question in a public forum where someone might possibly poke a little fun at it.
“Dirty little minds”? 
Put both flights in the “My Aircraft” box in your profile, then open up My FlightAware.
Flattening my forehead with a slap to it…gawd, that was easy…