XUL:Attribute:flags

flags: Type: space-separated list of the values below; A set of flags used for miscellaneous purposes. Two flags are defined, which may be the value of this attribute.

dont-test-empty: For template generated content, the builder will not check that a container is empty.
dont-build-content: This flag may be used on a tree to indicate that content elements should not be generated. This results in a performace enhancement, but you will not be able to use the DOM functions to retreive the tree rows.

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