"Parent Subcomponent" & "Parent Subproject" fields are causing parsing error when trying to export issue search results with XML export
It seems, that the root cause for this error is Parent subcomponents custom field, which is trying to chain components together with <br> tag. XML format needs the closing tag also, which is why this breaks the XML parser functionality. Please take a look at the response payload row 201 in attachment xml_error_br.
My second point about the special characters (&): Custom field should escape the & (and probably other special characters as well?) character, because Jira’s XML parser throws an error when it faces the unescaped character.
So to reproduce this in your demo environment, please create Parent subcomponents custom field and add it in to the test project. In our case this is breaking the Jira issue search’s XML export.
From our point of view this fix isn’t that critical anymore since we can fix it by deleting the custom field. I hope my report helps!