As you can see, tcblisting takes key-value arguments.  This breaks the
"mandatory arguments to verbatim environments" part of
`font-latex-syntactic-keywords', which is defined as:

    ;; After the optional argument, there may also be
    ;; another mandatory argument(s) (e.g. with VerbatimOut or
    ;; the minted envs or defined with `lstnewenvironment').
    "\\(?:{[^}]*}\\)*"

Since the key-value arguments _can_ contain braces (e.g., title={Example
shell session}), the regex does not match properly and messes up the
fontification.

Feel free to add "tcblisting" to `LaTeX-verbtaim-environments' and check
out the example above: You will see that everything after title={Example
shell session} is fontified as verbatim.

I would be happy to try and improve the regex so that it handles
key-value arguments, but I first wanted to ask if this is indeed and the
best approach.

Best regards,

-- 
Dario Gjorgjevski <dario.gjorgjevski@gmail.com>
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