Mixed content warning on admin panel.

[convenient]

Mixed Content: The page at 'https://example.com/index.php/admin/system_config/edit/section/payment/key/123456/' was loaded over HTTPS, but requested an insecure image 'http://i.imgur.com/nkD1M9R.png'. This content should also be served over HTTPS.

https://github.com/jreinke/magento-improve-api/blob/master/app/code/community/Bubble/Api/etc/system.xml#L5

The image is tightly coupled to imgur which seems odd, but it's hardcoded to request a http image which is causes a mixed content warning when the admin panel is on https.