Multiple custom fields not available in 'Grouped by'


I created two custom fields and I’m trying to use both of them on the ‘grouped by’ field. Both are available in the drop down list. When I select any one of them, the other one doesn’t show up on the list when I try to select it.

The issue only appears when multiple custom fields are used in ‘grouped by’, using both custom fields is ok on ‘filtered by’ and ‘view’

Currently running v0.27.1 on chrome Version 63.0.3239.84 (Official Build) (64-bit), Windows 7.