Lumira designer: filtering on linked dataources from Discovery

In Discover I pulled data from 1 universe and created 2 data sources (A and B).

I have linked those data sources in Discovery using a common dimension between the two.

Then, I pulled that into Designer for further design.

In Designer I am able to only do filters on A but not B. When pressing Ctrl+Space it shows only A dimensions.

But, when I go to Edit initial view I can see both A and B dimension listed in DS_1.

I need to filter on dimensions coming from B as well.

//98 is data source A in Discovery
DS_1.setFilter("DS:98,DIM:id_185", CROSSTAB_1.getSelectedMember("DS:98,DIM:id_185"));