Don't generate ancestors for MathML elements and filter out empty utterances
Don't generate ancestors for MathML elements and filter out empty utterances

chrys87/orca-beep,chrys87/orca-beep,GNOME/orca,chrys87/orca-beep,GNOME/orca,GNOME/orca,GNOME/orca,chrys87/orca-beep