4:2:2 and 4:4:4 chroma sampling are supported only in a degraded configuration. The following features should be fixed and re-enabled once bugs are resolved:

• inter frames (enabling causes faulty reconstruction output and decoding failure, related to tx size) ("there is some additional processing with sub8x8 motion compensation for 422 chroma")
  • sub-8x8 inter blocks
• LRF (enabling causes decoding failure for 4:2:2 input)
• CfL prediction (@barrbrain has indicated that it makes some assumptions about 4:2:0 sampling, but untested)
• Chroma 422 mode causes enc/dec mismatch and its test cannot detect this #1149 (desync caused by CDEF with 4:2:2 only)