Rough idle after filling tank

I have searched for this on the subreddit but I wanted to go a little more in depth on my question, and sorry I don't have a video.

I have a 22 BB with 70k miles and almost immediatelyafter filling the tank, it starts to idle rough, dropping 200-300 rpm and then going back up to normal 900ish. After driving it goes away and never comes back until the next fill up. I don't think its bad fuel as it happens after filling up from different places, and I'm hesitant to change the purge valve as it doesn't have the check engine light on. My initial thought was spark plugs, but I feel like it should be doing it all the time if it is the spark plugs? Thanks guys