src/vs/platform/terminal/node/ptyService.ts/XtermSerializer/setUnicodeVersion
class XtermSerializer:	async setUnicodeVersion(version: '6' | '11'): Promise<void> {
		if (this._xterm.unicode.activeVersion === version) {
			return;
		}
		if (version === '11') {
			this._unicodeAddon = new (await this._getUnicode11Constructor());
			this._xterm.loadAddon(this._unicodeAddon);
		} else {
			this._unicodeAddon?.dispose();
			this._unicodeAddon = undefined;
		}
		this._xterm.unicode.activeVersion = version;
	}