Known Limitations
Affected Services field not displaying service name
Unfortunately, there’s currently no Jira API to translate the value of the Affected Services field to the actual name of the Jira Service Management service. If you are using this field in your dashboard gadgets and would like to have the service name displayed, vote on this public feature request for Atlassian to implement this API.
Custom issue type icons not displaying for some users
Custom icons in Jira will only be displayed if the user has Browse projects permission for at least one project, the issue type avatar is used in. Read more on the technical background here.
For Firefox users, the Enhanced Tracking Protection feature of Firefox might be removing a necessary cookie for loading custom icons.
You can add your Jira URL to the exceptions, which should fix the error.