Sites with high volume of content may have some moved, deleted or badly referenced content. This situation will cause a 404 http error.
In high performance sites the previously described situation can be a resource problem. It is not necessary that we load completely the site to show a 404 error page.
Loading a plain HTML page will result easier for our web server than loading a complete CMS instance.
With a few lines of code we can hook the WordPress normal loading in order to determine if a 404 error has been produced. If we detect this situation we will make a redirection to a plain HTML page, interrupting the normal WordPress loading process.
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