I just re-read it, you're correct. It only covers React > For avoidance of doubt, no license is granted under Facebook's rights in any patent claims that are i

I just re-read it, you're correct. It only covers React > For avoidance of doubt, no license is granted under Facebook's rights in any patent claims that are infringed by (i) modifications to the Software made by you or any third party or (ii) the Software in combination with any software or other technology.