Hierarchical tree with keyboard navigation, expand/collapse state synchronisation, and pluggable node rendering. Bind items as a JS array; the WC owns the visible tree.
It has no shadow root. Anything you render into it — row templates, node templates, cell renderers — stays in the document, so your app's stylesheet, your own component styles and Bootstrap's utility classes reach it normally.
Its own CSS is scoped at build time onto a data-mps attribute, the same device Angular uses for _ngcontent, so it cannot leak out onto your markup.
The trade-off runs the other way: page CSS now reaches this component's internals, exactly as emulated encapsulation behaves everywhere else. ::part() and ::slotted() no longer address it — use ordinary CSS selectors instead.
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