I wonder if this error fixed... I have same error...
I'm very sorry, I never got around to fixing it on the desktop version. For now, you can use https://app.writerush.net/ which is the most up-to-date version. I have a new computer now, so I have to learn a new technology that will allow me to make a desktop app from it.
Thanks so much for bringing this to my attention! I will notify you when I update WriteRush!