Verbatim elements can be styled in a variety of ways, see Section 4.3, Verbatim styles. This function returns the highlight settings for a particular verbatim environment.

If the style for this environment is explicitly “plain”, then no highlight settings are returned (this avoids a bunch of warning messages). Otherwise, if a db processing instruction with a verbatim-highlight pseudo-attribute is present, it is returned. If there’s no PI, then the default settings for this kind of environment are returned.