What does "shirt courtesy of Jun" mean?
I can't understand the sentence mentioned above.

I got a message "just a happy day, shirt courtesy of Jun" with a photo.

In that sentence, I don't know what "courtesy" really means.

please help me!!!

Thank you.

Question

What does  "shirt courtesy of Jun" mean?
I can't understand the sentence mentioned above.

I got a message "just a happy day, shirt courtesy of Jun" with a photo.

In that sentence, I don't know what "courtesy" really means.

please help me!!!

Thank you.

Answer

'Courtesy of Jun' = I have Jun to thank for this shirt, Jun is responsible for the fact that I am wearing this shirt.
Jun either gave or sold him the shirt, or is the company that designed the shirt.

"Our flowers for this event come courtesy of the local flower store." = The local flower store probably donated the flowers.

Answer

It means that Jun sent you a shirt as a present.