Question about Muppet Album Performers

[SesameFever]

When the Muppets recorded studio albums like "Kermit Unpigged" or "Sesame Country" did the performers wear their costumes/hold their Muppet or just dress normal and sing in the character voice??? I am guessing no costumes because it is just an album after all.

 

[SesameFever]

No puppets invloved

Thanks