Is -Dlegacy supported for Flash target?

I have updated to OpenFL 3.6.0 (from 2.x.x) and that has increased my flash game by 20 KBs (must be a lot of new libraries?).

That’s not very much, still I’m trying to keep the base SWF size as small as possible. I’ve tried using -Dlegacy when compiling, but that seems to have no effect…

-Dlegacy has no effect on flash target, it’s only for native targets

I used an advice from here TextField.setTextFormat doesn't work on part of the field and did:

haxelib set openfl 2.2.8
haxelib set lime 2.1.3

Now the swf size is 30 KB smaller.