This answer record serves as the Vitis 2020.3 Release Notes and contains links to information about what is included in the update.
This update contains packages for the Vivado tool that is used to support Vitis.
For information regarding what was contained in the Vivado 2020.3 release, see (Xilinx Answer 76307)
For Vitis 2020.x Known issues see (Xilinx Answer 73646).
Please seek technical support via the Vitis, SDAccel and SDSoC Board. The Xilinx Forums are a great resource for technical support.
The entire Xilinx Community is available to help here, and you can ask questions and collaborate with Xilinx experts to get the solutions you need.