Same notes are not played when the other voice is muted

In the attached score, there are two voices on one staff in the same measure. Some of the notes are shared between the voices (both voices play the same note) and some notes are different between the voices.

When I mute voice 2 in the mixer, all notes from voice 1 are played correctly. However, if I instead mute voice 1, only the notes which are different from voice 1 are played. The ones that are shared with voice 1 are not played.

I expect all notes of voice 2 to be played when voice 2 is not muted.

I tested this with 3.0.4 on Kubuntu 18.04.