Newbie thinks he is in charge of identifying the team’s mistakes

We have a new staff who joined the team 6 months ago fresh out of college. He goes around the team checking anything that is ready to be delivered to the client and calling out minor edits he made, including work that the director approved. For example, he would say he hid a column or swapped a screenshot. He makes every effort to notify everyone in the group chat of the changes he made.

At first, people thought it was nice to have someone who was so enthusiastic about the work. Now it’s occurring on a daily basis and the team is getting annoyed.

On one occasion, our calculation was correct, but because he didn’t know, he made the update without asking. He later announced his revisions and caused rework.

I understand he wants to help and show he is capable of more responsibilities. His behavior also exhibits he lacks respect for the team dynamics and feels overly confident to show off.