playback with full orchestra same time as only viewing part

I started using Musescore 4. It looks great, and seems easy to use. Thank you for great work.
But, I just cant simply how I can make playback with full orchestra, sametime as I view a single part.
In musescore 3 there were a checkbox in the mixer that could turn on/off all other instruments, but it seems to have disappeared in musescore 4.