Unable to use jira gadget because the image placeholder returns not found error

[Ruud Visser]

Hi,

We have moved our confluence to new portal, first we had problem seeing the gadget but after changing the gadget url in the database that problem was solved. But if we select for example the JIRA gadget in macro selection dropdown, we see the pop-up but after clicking on ok to add the jira issue to the page nothing will happen. 

the only error what we see is: 

GET: https://<new URL>/placeholder/macro?definition=e2ppcmE6a2V5PU00LTM0NDUyfQ==&locale=en_GB 404 (Not Found)