Where was Joan Rivers in the Oscars' In Memoriam tribute?

Update: 

The Academy issued a statement about Rivers' absence from the tribute:
"Joan Rivers is among the many worthy artists and filmmakers we were unfortunately unable to feature in the In Memoriam segment of this year's Oscar show. She is, however, included in our In Memoriam gallery on Oscar.com."
Original story:

Joan Rivers certainly was a polarizing figure when she was alive, earning the ire of the thousands of celebrities whose outfits she tore apart on E!'s Fashion Police. And even when she passed away in September, many Hollywood celebs didn't know how to react. But leaving her out of the Oscars' annual In Memoriam tribute is completely out of line.

Twitter noticed the omission right away and called the Oscars out on it

Our Paste BN reporters noticed

And several celebrities stepped into to shame the Academy