Board Thread:In-Editor Help Assistance/@comment-25108241-20191129142245/@comment-9605025-20191201175203

Which template is the character infobox? The link you gave leads to a non-existant page. With portable infoboxes, you should be able to customize appearance (including colors) for a limited number of instances by using either (or a combination of) the type, theme, or theme-source attribute.