src/vs/workbench/contrib/notebook/browser/contrib/viewportCustomMarkdown/viewportCustomMarkdown.ts/NotebookViewportContribution/_warmupViewportNow
class NotebookViewportContribution:	private _warmupViewportNow() {
		if (this._notebookEditor.isDisposed) {
			return;
		}

		if (!this._notebookEditor.hasModel()) {
			return;
		}

		const visibleRanges = this._notebookEditor.getVisibleRangesPlusViewportAboveAndBelow();
		cellRangesToIndexes(visibleRanges).forEach(index => {
			const cell = this._notebookEditor.cellAt(index);

			if (cell?.cellKind === CellKind.Markup && cell?.getEditState() === CellEditState.Preview && !cell.isInputCollapsed) {
				(this._notebookEditor as INotebookEditorDelegate).createMarkupPreview(cell);
			} else if (cell?.cellKind === CellKind.Code) {
				this._renderCell((cell as CodeCellViewModel));
			}
		});
	}