Enabling OpenCL GPU rendering for Cycles on Linux? I followed the answer on this question for blender 2.7x, but I still don't see the option to enable GPU rendering for cycles, as shown in this screenshot: 



I'm using an RX 560 on Debian 11


contrib non-free enabled in my sources.list
CYCLES_OPENCL_SPLIT_KERNEL_TEST=1 inside /etc/environment 
ocl-icd-opencl-dev installed


How do I enable GPU Cycles rendering?
To enable opencl on linux working with blender, the only way is to install the official amd-pro driver, or, as I did, only the opencl part.
Unfortunately, the only Linux distro officially supported are:
RHEL 8.0 / CentOS 8.0 and 7
Ubuntu 18.04.3 (and derivative) (so, all the kubuntu, xubuntu, lubuntu etc and mint)
SLED/SLES 15 SP1 (and opensuse leap)

So, with Debian You are in a bad spot, unless You play around quite a bit