We have upgraded our Jira Core from 8.7 to 8.19.
Afterwards, Jira Service Desk would not retrieve emails anymore. When heading to the email requests for the project, we saw that we weren't able to configure the email requests anymore because the window wasn't loading properly. We have checked multiple browsers, we have removed addons for the browsers, we have ran the browsers in safe mode, we have rebooted the server, but nothing comes up. We do however notice in developer mode of Chrome that the divs of the window are loaded. It's just not displayed.
Included is a screenshot.