Created attachment 188654 [details] Legend with title ODF has an optional <text:p> child element of the <chart:legend> element. If it exists, it is a title of the legend. LibreOffice currently ignores this legend title.
Thanks Regina! Reproduced in: Version: 24.2.0.0.alpha0+ (X86_64) / LibreOffice Community Build ID: 42364fbfafaa95773c073cc080142b64ec1786fb CPU threads: 8; OS: Linux 5.15; UI render: default; VCL: gtk3 Locale: en-AU (en_AU.UTF-8); UI: en-US Calc: threaded https://docs.oasis-open.org/office/OpenDocument/v1.3/os/part3-schema/OpenDocument-v1.3-os-part3-schema.html#element-chart_legend