As the pair perfectly played the melody, fans were able to get a glimpse inside Courteney's glamorous living room, which featured a lot of house plants.
As the camera panned around Courteney's house, fans were able to glimpse a whole host of indoor plants, alongside a guitar, beautiful grey sofa and a grated fireplace with a mounted television hanging over it.
WATCH: Courteney Cox shows off piano skills inside lavish living room
The room also featured a wide variety of different lamps, one next to the sofa, another on the other side of the room and a third seated above Courteney's piano.
Reflected in one of the star's windows was a large ring light, which was providing the lighting for her latest video.
The Scream star had previously played the Harry Styles song Sunflower, Vol. 6 and it drove both her and Harry's fans wild.
Referencing this in her caption, the actress teased: "You asked for it…"
Courteney's lavish living room featured many indoor plants
And her fans were blown away with her rendition, with one comparing her to a legendary singer, saying: "You're killing me! Tori Amos watch out!!"
Another referenced Harry Styles, saying: "Harry is probably fangirling rn," while others suggested that the famous singer was "crying" or was going to "freak out."
One fan added: "Courteney & Harry *chef's kiss*" while a different heart-warming post said: "My idol singing a song by my other idol is truly the best thing ever."
And a very excited fan added: "I JUST OPENED UP INSTAGRAM TO THIS?!! THIS IS AMAZING!"
One fan looking forward to the next time said: "I've said it so many times but your piano covers are my favorite kind of posts."
The star is BFFs with Jennifer Aniston
The Friends star is BFFs with co-star Jennifer Aniston, and she recently revealed the incredibly sweet nickname she has for her.
In a post celebrating Jennifer's recent birthday, the star highlighted the longevity of their relationship, saying: "Happy birthday Jenny Louise! We've known each other so long I don't even know why I call you that. I love you!"
Courteney's post, which also included a throwback snap of the pair, attracted a massive fan reaction, with many hailing the pair's friendship.
The Office star Mindy Kaling called them a "killer duo" while another labelled them as "friendship goals", enthusing: "My two favorite women in the entire world <3. I love you both so much!!"
One passionate fan added: "YOUR FIRENDSHIP IS MY FAVOURITE THING IN THE WHOLE WORLD!"
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