Add library does not update pom.xml

Hi
IDEA detects the missing class in persistence.xml.
As you can see from the screenshot, IDEA finds the required maven dependency which contain missing class. But when I select "Add library", my pom.xml is not updated. Instead, the required dependency is added as a project dependency. IDEA does not synchronize its dependency configuration with pom.xml. This seems to be a bug, isn't it?