This question is a follow up to verbatim-like environment with optional arguments poorly behaved. Based on David Carlisle's suggestion, I manually looked for an optional argument and employed ...
[EDITED to show where I actually want to use the optional argument] This question may be answered at How to pass an optional argument to an environment with verbatim content?, but I'm having a hard ...
This is an attempt to make clear what happened in this question of xport (now deleted, sorry). The now deleted question included code that tried to make my answer to this question of xport work for ...