I watch Three’s Company on Pluto TV with subtitles on which is how I noticed this. The lyrics are occasionally different and it happens in both the early seasons and the later ones.

The line goes:
“Life is a ball again”
will occasionally change to:
“Life is a frolic”

I am wondering if anyone else noticed this. The only reason I noticed this is because I was reading the subtitles.

Season 7 episode 1. The episode “A night not to remember” is one such example.