We setup a site recently and I experienced a “Cannot decode raw data” error in Safari on iOS for both the iPhone and iPad.
We have a caching plugin installed on the site on WordPress called WP Super Cache and I immediately assumed that this had something to do with it. Clearing the cache or even disabling the plugin solved the problem.
It came down to the “Compress pages so theyâ€™re served more quickly to visitors.” setting which turns on Gzip compression using PHP ob_gzhandler when in PHP mode.
The only solution for us was to turn off this “Compress pages so theyâ€™re served more quickly to visitors.” setting for now. We tried legacy, PHP and mod_rewrite caching with different settings but nothing solved the issue other than turning off the setting.