Custom page tab is empty

My application used to work as custom tab on FB page, but currently it doesn't load when I click on tab, there is even no request to my server. Application itself is ok, I checked both secure and non-secure c开发者_Python百科anvas URLs and page URLs.

Is there any way to find out what is going on? Logs/debug mode/etc?

If you are using Chrome, right click on the fan page and select "Inspect Element". Go to the Network panel and find out your server connection status. Click on it to get further information(headers, cookies, timing, etc).

My localhost server example:

If you are using Firefox, you can install Firebug and do the same thing.

I had the same issue a few minutes ago. Turns out Facebook doesnt even try to load your iframe if the user is on FACEBOOK via HTTP, regardless of whether your application uses HTTPS.

So I changed my web browser's URL.

Old: http://www.facebook.com/<page>/app_<appID>
New: https://www.facebook.com/<page>/app_<appID>

Edit: What it seems that I originally had messed up was that in the application settings I had entered the HTTP URL in both the HTTP and the HTTPS fields. See http://d.pr/i/ARGF

This setting can be changed here: https://developers.facebook.com/apps/your app ID/summary

In case anyone else is having this problem - in my case, the problem turned out to be a trailing space in my Secure Page Tab URL.

Make sure you have no leading or trailing spaces for any of the urls.

Very lame.