Epic Link custom fields edit html is not correct

In JIRA Service Desk, you can set a default value for unsupported fields added to a request type.

For the Epic Link field, this worked correctly in JIRA 6.4.

However, in JIRA 7.0.0 this is not working.

Doing some debugging, It seems that the edit html returned from the Epic Link custom field has not changed. It was for 6.4 and now for 7.0.0 the same, ie.

                            <div class="field-group aui-field-labelpicker" >
                                                                        <label for="customfield_10506">Epic Link</label>
                
    <fieldset class="hidden epicpicker-params">
        <input type="hidden" title="id" value="customfield_10506">
            </fieldset>
    <div id="js-customfield_10506-ss-container">
        <select class="single-select long-field hidden js-epic-picker"
                id="customfield_10506"
                name="customfield_10506"
                            data-container-class="long-field"
                data-project-key="ONE"
                >
                    </select>
    </div>



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But with the release of 7.0.0, whatever extra processing happens (as the final html in the browser is very different when running JIRA 6.4) is not happening for plugins in 7.0.0

Reproduce

1. Instance with JIRA Software and JIRA Service Desk applications
2. Create a Service Desk project
3. Use a field screen that has Epic Link on the create screen
4. Go to Project Administration for service desk project -> Request Types
5. Edit fields for the request type
6. Add a new field (Epic Link)
7. Observe that it is added as a hidden field and requesting to preset a value
8. Click Edit value

Expected outcome

• Like in JIRA 6.4, you can select an Epic from the list

Actual outcome

• No dropdown select box is there, the html appears to be missing and therefore does not work

Workaround

No workaround, except removing Epic Link from the request type fields