When using QGIS 2.8.2, I am unable join a table to a layer that has a feature subset (Layer Properties > General > Feature Subset).
For example, creating a feature subset on a layer prior to joining an attribute table to that layer always results in no joined records.
Conversely, I cannot create a feature subset on a layer after joining an attribute table to that layer because the feature subset query builder button is greyed out.
Thus, I cannot combine Feature Subsets with table joins.
This appears to be a bug, or am I missing something?