@OneEagle Thank you so much for your prompt and comprehensive reply.

Overall, php 8.1.8 (the one I have) runs smoothly, with few exception here and there, which I am not sure if they due to the php version or some other issues with UNA, that's why I keep posting and asking them. What is the definition of "compatibility issues"? any particular test I need to do on my sites to pick those up? tnx