"cavil". I have never seen or heard anyone use this word. Useful word nonetheless.
To “cavil” is to engage in an argument that borders on bad faith. It may be an argument made in good faith, but over trivialities or petty concerns few others take seriously. In the 17th century, Dr. Samuel Johnson defined the verb as “raising frivolous objections.” Unfortunately, frivolity is in the mind of the speaker; often a person who chooses to cavil feels they are making a significant argument concerning a subject of importance to them. Caviling ultimately results in an argument that few but the person making it believe is worth their time or trouble.