WebKit2.NavigationPolicyDecision.modifiers
NavigationPolicyDecision.modifiers: Number(guint) (Read)
If the navigation associated with this policy decision was originally triggered by a mouse event, this property contains a bitmask of various Gdk.ModifierType values describing the modifiers used for that click. If the navigation was not triggered by a mouse event or no modifiers were active, the value of this property will be zero.