How can I add X-Frame-Options selectively using Apache?

I am planning to set X-Frame-Options SAMEORIGIN in my server’s httpd.conf as part of improving the defenses against click jacking. I understand this will add the X-Frame-Options header to all pages. There is a “widget” page that I would like to exempt from this (other sites will display this page inside an IFRAME).

Is there a way to configure Apache 2 to not send the header for a specific page alone?

Yes, use SetEnvIf:

SetEnvIf Request_URI "^/my_awesome_widget_page.html$" iframes_are_cool
Header set X-Frame-Options SAMEORIGIN env=!iframes_are_cool

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