The goal: On my local test server (MAMP Pro), use an iframe in a wordpress page to load a local html file, so I can design html content locally without needing to paste it into wordpress after every change for testing. Simple, right?
The problem: The iframe returns my wordpress install's 404 error page. While attempting to debug this, I found that, in the markup, the iframe is formatted correctly, but when I right-click on the iframe and load it in a new browser tab, the url bar says "http://(my wordpress install path)/Array" regardless of the url the iframe is pointing to. If I disable pretty permalinks (and go back to the default "?p=123" style) the iframes work perfectly.
So it looks like WordPress is intercepting the iframe url, trying to rewrite it, and failing. I'm not sure what to do about this.
Any help will be appreciated.