The order actually says that the AG is to prioritize enforcement of civil and criminal laws against flag burners when they ALSO violate applicable, content-neutral laws that cause harm "unrelated to expression." In other words, exactly what Johnson said you could do. www.uscourts.gov/about-federa...
If you steal a flag to burn, you can be prosecuted for stealing the flag that you burned. If your flag burning lights a building on fire, you're catching an arson charge (and probably civil liability to boot). The point is, if you violate another law while flag burning, Johnson doesn't save you.
All Johnson protects is the symbolic act of flag burning itself. The government is still free to regulate the time, place, and manner at which you can set things on fire, even if that firebuggery is expressive. Because those are CONTENT-NEUTRAL regulations.
Section 2(b) of the order says just that: if the DOJ finds that an instance of flag burning violated state or local regulations, then the DOJ is to refer the matter to the appropriate authority. Again, perfectly consistent with existing DOJ power (if a bit waste-of-timey).
Section 2(d) is more troubling, because it relates to the denial or revocation of immigration documents for merely engaging in expressive conduct. Yes, the First Amendment applies to foreigners and those here on visas. I'd suggest someone read Reno v. Am-Arab Discrim. Committee, probably twice.
In other words, the executive order doesn't do shit, directs the DOJ to do the things it could already do, and in general is a big showy bit of cockery that no one ought to pay any real attention to, except to burn a flag (that you legally purchased) in a manner consistent with local regulations.
For no other reason that it will make Donald Trump and his supporters v v buttmad, and that's always a positive good.
A concept the right seemed determined to ignore when Tarrio was convicted. "So it's illegal to burn a BLM flag, but not a US flag?" He stole the flag and then burned it! It was regular old malicious mischief.