When editing a post it is rather common to find something like: "hyperref creates a problem" as title of the question or (concrete example from the list of newest questions) "latexdiff and lstlisting". Should we add a capital letter if the package name is the first word of the title (or more generally a sentence)? For the visual consistency I would say yes we should, but on the other hand it might be better to stick to the real way of writing the name of the package, so that is why I am referring to the specialists here.
I would add something like "Package" or "Class" to use the correct call with
To change only the first letter of a heading to an capital letter is no good practice. Do it only if the post needs improvement too or has to be retagged.