Mural artist Tee2sugars has since gone back and reinstated the mural to its former glory.
He remained positive about the vandalism, which he said he “half expects” to happen.
“They want you to be sad about it, so I don’t let it get to me.
“It’s paint at the end of the day, and I have fixed it now to make people happy again.”
He shared a video on his social media page featuring the vandals, stating: “I’m open to collabs, but not like this.”
Gavin and Stacey co-creators Ruth Jones and James Corden announced earlier this year that the show would return for one final episode, to be broadcast on Christmas Day.