diff --git a/Help/release/dev/FindFLEX-DEFINES_FILE.rst b/Help/release/dev/FindFLEX-DEFINES_FILE.rst
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+FindFLEX-DEFINES_FILE
+---------------------
+
+* The :module:`FindFLEX` module ``FLEX_TARGET`` macro learned a
+  new ``DEFINES_FILE`` option to specify a custom output header
+  to be generated.