Function ghost_button_flat 

pub fn ghost_button_flat(theme: &Theme, _status: Status) -> Style

Like ghost_button, but never paints a background of its own — even while hovered or pressed. Used for buttons embedded inside a larger row whose background is already driven by external state (e.g. the commit message row, whose full-row highlight is controlled by row_style! on the surrounding container based on hover/selection/range state). Without this, the button’s own native hover background would compete with — and visually desync from — the row’s state-driven highlight.