After an upgrade of the macOS SDK used to build the JDK, the behavior of the `apple.awt.brushMetalLook` and `textured` Swing properties has changed. When these properties are set, the title of the frame is still visible.
It is recommended that the `apple.awt.transparentTitleBar` property be set to `true` to make the title of the frame invisible again. The `apple.awt.fullWindowContent` property can also be used.

Please note that `Textured window` support was implemented by using the `NSTexturedBackgroundWindowMask` value of `NSWindowStyleMask`. However, this was deprecated in macOS 10.12 along with `NSWindowStyleMaskTexturedBackground`, which was deprecated in macOS 10.14.

For additional information, refer to the following documentation:
 - `apple.awt.brushMetalLook`: https://developer.apple.com/documentation/appkit/nstexturedbackgroundwindowmask?language=objc
 - `apple.awt.transparentTitleBar`: https://developer.apple.com/documentation/appkit/nswindow/1419167-titlebarappearstransparent?language=objc
 - `apple.awt.fullWindowContent`: https://developer.apple.com/documentation/appkit/nsfullsizecontentviewwindowmask