I use QGIS 2.14.1.
I add vector layer from UTF-8 encoded geojson, which is read fine and attribute table show correct characters.
If I use QGIS algorithm on this layer (i.e. clip, voronoi, etc) I get new layer which attribute table is full of question marks instead correct characters.
If I use SAGA algorithm (i.e. clip) characters in newly created layer are fine.
Is there some setting I'm missing?