I\'m a bit confused about this. I\'m hoping it\'s something wildly obvious I\'ve missed! I have a very simple form:
Thanks to the comments to my question I have found the answer to be in apache configuration. It appears that, because the index.php file is inside a folder called page, apache will automatically redirect to the page with a slash on it. This is the default setting as seen in the Apache directorySlash documentation.
As they warn against turning this off, I will just change the url to what I'm posting. Alternatively, of course, I could add a .htaccess file with proper rewrite rules setup.\
Thanks for everyone's help! As a side note, Safari's inspector left me a little wanting in this case. Chrome turned out to be a far better option for testing.