Flexform labels can be customized for the editor in the backend. You often see information online that flexforms for plugins can be customized in PageTSconfig as follows:
TCEFORM.tt_content.pi_flexform.[ext_key].[sheet_key].[field_key] {
....
}
But the trick is in the detail.
What must be used for [ext_key].[sheet_key].[field_key]?
For [ext_key], the extension key must be entered, specifying the view (_pi1). Example:
TCEFORM.tt_content.pi_flexform.rgtabs_pi1.....
For the extension tt_news, however, the number 9 ( tt_content.list.20.9.0 =< plugin.tt_news ) must be used instead of the extension key for historical reasons. Example:
TCEFORM.tt_content.pi_flexform.9.sDEF.listOrderBy.removeItems = author
The [sheet_key] is the key for the tab, e.g. sDEV. It can be read with developer tools in the browser (e.g. Firebug for Firefox) by clicking on the element that is to be customized.
The [field_key] can also be read with developer tools in the browser.