src/vs/editor/browser/controller/textAreaHandler.ts/VisibleTextAreaData/definePresentation
class VisibleTextAreaData:	definePresentation(tokenPresentation: ITokenPresentation | null): ITokenPresentation {
		if (!this._previousPresentation) {
			// To avoid flickering, once set, always reuse a presentation throughout the entire IME session
			if (tokenPresentation) {
				this._previousPresentation = tokenPresentation;
			} else {
				this._previousPresentation = {
					foreground: ColorId.DefaultForeground,
					italic: false,
					bold: false,
					underline: false,
					strikethrough: false,
				};
			}
		}
		return this._previousPresentation;
	}