Fired in the following cases:
- when an attribute has been added, changed, or removed from a node,
- when a node with an attribute is inserted,
- when a collapsed model selection attribute is converted.
attribute is a namespace for a class of events. Names of actually called events follow this pattern:
attributeKey is the key of added/changed/removed attribute.
name is either
'$text' if change was on a text node,
or the name of element which attribute has changed.
This way listeners can either listen to a general
attribute:bold event or specific event (for example