src/vs/editor/contrib/unicodeHighlighter/browser/unicodeHighlighter.ts/DocumentUnicodeHighlighter/_update
class DocumentUnicodeHighlighter:	private _update(): void {
		if (this._model.isDisposed()) {
			return;
		}

		if (!this._model.mightContainNonBasicASCII()) {
			this._decorationIds = new Set(this._editor.deltaDecorations(Array.from(this._decorationIds), []));
			return;
		}

		const modelVersionId = this._model.getVersionId();
		this._editorWorkerService
			.computedUnicodeHighlights(this._model.uri, this._options)
			.then((info) => {
				if (this._model.isDisposed()) {
					return;
				}
				if (this._model.getVersionId() !== modelVersionId) {
					// model changed in the meantime
					return;
				}
				this._updateState(info);

				const decorations: IModelDeltaDecoration[] = [];
				if (!info.hasMore) {
					// Don't show decoration if there are too many.
					// In this case, a banner is shown.
					for (const range of info.ranges) {
						decorations.push({
							range: range,
							options: Decorations.instance.getDecorationFromOptions(this._options),
						});
					}
				}
				this._decorationIds = new Set(this._editor.deltaDecorations(
					Array.from(this._decorationIds),
					decorations
				));
			});
	}