A lot of issues have been arisen after the update.
1. Wi-fi disconnection problem
2. Apps have become slow
3. Bluetooth is not working properly.
4. App crashes.
Here is the solution with every major update of Android i make sure i factory reset my phone after the update, Yes you have to setup your phone again but you will not have to go through alot of bugs. I don't have any bugs with the latest update because i did factory reset my phone after the update.