1. In the middle of answering a question, it suddenly turns white. I can't see anything. All of my answers are invisible. 2. Your answer becomes invalid because of something "Rude", and you will not know what word is restricted. So I need to adjust the letters one by one and sometimes, I just cancel answering. 3. In comments, you have to click the notification panel or exit then go back again to the comment section to update the convo. 4. A lot of mathematical symbol are missing in calculator