Create a mask, set Sample to Current Layer, click in Layer mask, sample
In other versions of Photoshop, when the Eyedropper tool's Sample is set to Current Layer, the Eyedropper selects the black and white values of the Mask. In Photoshop Beta, it's ignoring the mask and sampling from the masked image. This is undesired. Sometimes we have to paint the mask and color sampling makes this much easier.
Had this problem in Beta 24.7.0 and just updated to Beta 24.7.0 (!? There was an update to Beta 24.7.0 in Creative Cloud but the version number was the same after the update). The issue is still present! MacOS 13.4.1