Description of problem:
file returns "text/x-c+" for an HTML file that contains a C+ code example.

Version-Release number of selected component (if applicable):
file-5.11

How reproducible:
Every time

Steps to Reproduce:
1. file --mime-type <file>.html

Actual results:
<file>.html: text/x-c++

Expected results:
<file>.html: text/html

Additional info:
Invoking xdg-open on an unrecognized windowing system invokes xdg-mime which, in turn, invokes this file command. The result is that xdg-open opens the file in a text editor instead of in a web browser.

This flow works on most of my .html files, but fails on the attached html files.

I found that disrupting the keywords in the code sample included in the file - e.g., inserting a space in the middle of the first instances of "template", "class", "private", and "public" in the attached file, caused file to return the desired mime type.