Excessive CPU usage when GroupRenderMode is set to Flat, RowDetailsTemplate is used and RowDetailsVisibilityMode is set to Visible. This issue is not reproduced only with Material, Office2016, Office2016Touch and Windows8Touch themes.
Hi, The fix will be available in our next official version – R3 2018 SP1, scheduled for 17-th October 2018 (Wednesday). Best regards, Ralitsa Kumanova