Until Qt 5.15, PlaceholderText color was automatically derived from the Text color, dimmed by 50% (set alpha to 128, assuming the text color is fully opaque). This method has been adapted in the static qt_fusionPalette() method. No other static method to populate palettes defines a PlaceholderText color. As a consequence, the Text color is used to render placeholder text characters. This patch adds a static method, that sets missing PlaceholderText colors by deriving them from the corresponding Text color. It takes a dim factor by which the opacity is reduced versus the corresponding Text color. Fixes: QTBUG-105049 Pick-to: 6.4 6.3 6.2 Change-Id: Iebb9d15d56f5d72d7ec68b7a0babdf5825b92665 Reviewed-by: Paul Wicking <paul.wicking@qt.io>