src/vs/editor/contrib/unicodeHighlighter/browser/unicodeHighlighter.ts/ViewportUnicodeHighlighter/constructor
class ViewportUnicodeHighlighter:	constructor(
		private readonly _editor: IActiveCodeEditor,
		private readonly _options: UnicodeHighlighterOptions,
		private readonly _updateState: (state: IUnicodeHighlightsResult | null) => void,
	) {
		super();

		this._updateSoon = this._register(new RunOnceScheduler(() => this._update(), 250));

		this._register(this._editor.onDidLayoutChange(() => {
			this._updateSoon.schedule();
		}));
		this._register(this._editor.onDidScrollChange(() => {
			this._updateSoon.schedule();
		}));
		this._register(this._editor.onDidChangeHiddenAreas(() => {
			this._updateSoon.schedule();
		}));
		this._register(this._editor.onDidChangeModelContent(() => {
			this._updateSoon.schedule();
		}));

		this._updateSoon.schedule();
	}