Random "You Making Loving Fun" question

[bucklind17]

On the Rosebud documentary, the end of "You Make Loving Fun" goes something like:

LB: Ooh, yeah, you make loving fun
CM/SN: I'm beginning to wonder why
LB: Ooh, yeah, you make loving fun
CM/SN: I've feeling it's time to try

Lather, rinse, repeat followed by a nifty little guitar bit.

In a live Rumours tour version of the song (Oklahoma City, to be exact), the song ends the way it does on the album, with the "you making loving fun, it's all I want to do" lyric.

Does anyone know exactly when/why this changed? I don't suppose there are any studio versions of the song with the first lyric, which I really like and prefer to what ended up on the album? Did they ever perform the song Rosebud-style live after Rumours came out?