There is a sort of fifth verse. Written In or about 1861 by Oliver Wendel Holmes, father of the Justice Oliver Wendel Holmes.
There are copies of some broadsheets and sheet music in the Library of Congress containing the "fifth Verse." However one must pay for them. About six years ago I spent days doing an internet search for "Fifth Verse" and actually found it. Needless to say I have since lost it.
Finally found it here.
Probably the best known additional stanza was written by Oliver-Wendell Holmes during the Civil War, and was intended to decry treasonable acts against the US flag:
When our land is illumined with liberty's smile,
If a foe from within strikes a blow at her glory,
Down, down with the traitor that tries to defile
The flag of the stars, and the page of her story!
By the millions unchained,
Who their birthright have gained
We will keep her bright blazon forever unstained;
And the star-spangled banner in triumph shall wave,
While the land of the free is the home of the brave.
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The "foe from within" reminds me of Michael Savage's "the enemy within".