To allow any element add 'NO_ERRORS_SCHEMA' to the '@NgModule.schemas' of this component.] code example
Example: add 'no_errors_schema' to the '@ngmodule.schemas'
schemas: [
CUSTOM_ELEMENTS_SCHEMA,
NO_ERRORS_SCHEMA
]
schemas: [
CUSTOM_ELEMENTS_SCHEMA,
NO_ERRORS_SCHEMA
]