Hi Ihor,

> Timothy, looking at the new implementation of org-latex-src-block, I do
> not see custom-env being passed as an argument of
> org-latex-src-block–custom. This is likely a bug.

Ah yes, this was an oversight. Corrected in 30953bd7b701c870152cd60f52f2d484970caeb9.

All the best,
Timothy