As an alternative for this idea: Some improvements on visibility of open documents | Thinkwise Community
I thought I might be able to use a badge to achieve the same result. I looked very promising, until I realized badges only know the context of the possible parent relations, not the subject itself (other than @variant_id).
If we had access to the subject’s context, like the selected row’s primary keys, or the column filters (set by the “Change filters” process action), badges could be much more versatile.