Ponies who have definitely farted in public and would do so canonically of given the chance · 7:38am Jan 17th, 2019
Just to make it clear where I stand.
Rainbow Dash - Duh.
Pinkie Pie - Canonically finds fart humor funny as of 28 Pranks Later. Childish sense of humor and a constantly-on wild side. I think it's no question she's farted out loud in front of the rest of the Mane 6 - and proudly - at least once.
Applejack - Uncouth tomboy. Literally raised in a barn. Proud of her younger sister's burp in Sisterhooves Social so farting is most definitely not taboo to her.