You can recognise that flag as much as you want, it does not bestow any legal status upon it. Can we include other unofficial flags in the infobox? Northern Ireland does not have a flag that uniquely represents it, and the Ulster Banner is an unofficial flag. If an unofficial flag does in the infobox it gives undue weight to the flag. There is no "tug of war", the editor who restored the flag without consensus has this to say on the matter:

I can see right away that the official flag of Northern Ireland is going to cause controversy. There are two options: 1) That this is an encyclopedia, and we stick with the correct information or 2) We appease a minority of people by changing the flag to the defunct Northern Ireland flag.. some of whom will still not accept that flag either.

The emblem of the Northern Ireland Assembly is just that - an emblem used by that body. The proposed flags have not yet been adopted and so are not official.

This leads me back to the two suggestions above - the official flag of Northern Ireland (the Union Jack), or the unofficial Northern Ireland Flag. I do not want to purposely cause offence (though it seems to me that anyone likely to be offended by the official flag would also refuse to accept the existance of Northern Ireland in the first place), but I do want to include factual information in this encyclopedia.

Note that he claims the flag is both unofficial and defunct. Obviously his option 1 is the correct option, we stick to correct information.  We've already had outside opinions before (see above), and they unanimously said that as there is no official flag, no flag goes in the infobox. 303