Echo boiling gas

I have an Echo cs 590, 20" chain. I bought it in April, 2020 and have used it for maybe 4 tanks of gas. (I can't track time spans very well.)
 
Yesterday, I ran out of gas while using the saw. When I went to refuel the gas literally boiled. I waited for the saw to cool off and refueled with fresh gas. It will not start now. Using starter fluid it will rev a bit but not run.
 
I don't know if this is connected to my problem or not: At about tank 3 the chain came off during use because the cover nuts came loose. I had not thought to check them on a new saw. The chain got a little tweaked, so I filed off some burrs on the drive links and went back to work. It seemed to run just fine.
 
The saw has started very reliably on the fifth un-choked pull almost every time. Looking at this and other fora, boiling gas is unusual and even more so in a new saw.  I can't think of anything I might have done to cause the problem (my first approach to any mechanical issue). The work I was doing was cutting up an alder stump, and the wood is hard for alder. 
 
I am mechanically inclined, but do not have a lot of specific knowledge about 2 stroke engines much less Echos, so any advice troubleshooting the problem will be appreciated. I'd just bring it in for repair, but I need to use it and repairs this time of year take forever. I am guessing the problem is crud in the carburetor, but I'd like to know thats the problem before tearing into it. I'd probably order a new carb if thats the fix.
 
Most of all I need to make sure this does not happen again.
 
Any advice will be appreciated.