The headline from Mondoweiss (via Haaretz) read,

150 American actors, writers, directors and artists support Israeli actors’ West Bank settlement boycott  

More than 150 American actors, writers, directors and other artists signed a letter of support for the Israeli actors who declared they would not perform in Ariel, located in the West Bank.

Among them are well known TV actress Cynthia Nixon, playwright Tony Kushner, 21-time Tony winner for productions of “The Pajama Game” to “Phantom of the Opera” Harold Prince, star of the film “Yentl,” Mandy Patinkin, and Cameri co-founder Theodore Bikel.

The actual letter with the list of signatories has yet to be published.
Another headline, Israeli academicians join West Bank settlement boycott, also informed that around 150 Israeli academicians, authors and artists have joined the boycott by Israeli actors against performing in West Bank settlements.