Synonyms that are in the dictionary are marked in green. Synonyms that are not in the dictionary are marked in red.
Antonyms that are in the dictionary are marked in green. Antonyms that are not in the dictionary are marked in red.
One user mentions that this glitch is related to some specific pro-tuned weapons and their attachments, but claims that it supposedly got fixed in the latest update for the game.
Source: https://gamerant.com/call-of-duty-modern-warfare-2-spawn-3-guns/