Access-control-Allow-origin missin

Hello,

Thank you for reaching out regarding the CORS issue on your page. From the error you mentioned, it seems that the Access-Control-Allow-Origin header is not being sent in some cases, particularly on macOS Firefox and iOS Safari.

Here are a few steps to resolve this issue:

1. Server Configuration: If the plugin is set up correctly but the error persists, there might be a server-level configuration overriding the headers. Check your server’s .htaccess file or equivalent to confirm that there are no conflicting CORS rules.
2. Check for HTTPS Enforcement: Ensure that both the source and destination URLs use https://. Some browsers, especially Safari on iOS, enforce stricter rules for mixed-content handling.
3. Browser-Specific Issues: As noted, some browser variations can handle CORS differently. To address this:
   • Ensure your WordPress site and the external API both send the Vary: Origin header.
   • Use a wildcard * for Access-Control-Allow-Origin only if your use case does not involve credentials (e.g., cookies, HTTP authentication).
4. Debugging Tools: Use browser developer tools or plugins to inspect the HTTP headers. Look for:
   • Access-Control-Allow-Origin is present.
   • Any potential server-side cache interfering with the headers.
5. Plugin Debugging: Activate the plugin’s debugging mode if available. Alternatively, modify the code in enable-cors.php to log incoming requests and headers.
6. Testing Your Setup: Follow the steps in the readme.txt under the “Testing Your Setup” section to verify the functionality with a simple source-target setup.

If you’ve tried the above and still encounter the issue, let me know. I can guide you further or assist in debugging directly.

Best regards,
Kabir

Since we haven’t received a response from you, I’m proceeding to close this thread. Please know that you’re welcome to contribute to this thread at any time by adding your message.