diff --git a/README.macOS.md b/README.macOS.md
index 60c5441f2..7619ed056 100644
--- a/README.macOS.md
+++ b/README.macOS.md
@@ -315,8 +315,10 @@ declare several extensions.
- Call function fl\_open\_callback() at the beginning of your main() function to set
what function will be called when a file is dropped on the application icon.
-- In Xcode, set the "Info.plist File" build setting of your target application
-to the Info.plist file you have prepared.
+- In Xcode, set the `Info.plist File` build setting of your target application
+to the *Info.plist* file you have prepared. Alternatively, use CMake's
+`set_target_properties` function and `MACOSX_BUNDLE_INFO_PLIST` property
+to have CMake put your *Info.plist* file in the resulting macOS application bundle.
- Rebuild your application.
diff --git a/src/Fl.cxx b/src/Fl.cxx
index 818efe39d..ca0676f62 100644
--- a/src/Fl.cxx
+++ b/src/Fl.cxx
@@ -2328,6 +2328,11 @@ FL_EXPORT Window fl_xid_(const Fl_Window *w) {
to be effective for files dropped on the application icon at launch time.
It can also be called at any point to change the function used to open dropped files.
A call with a NULL argument, after a previous call, makes the app ignore files dropped later.
+
+ Use of this function also requires the application bundle's \c Info.plist file
+ to declare what file types are allowed to be dropped on the icon. File \c README.macOS.md
+ describes how to do that in its section
+ Make an Application Launchable by Dropping Files on its Icon.
*/
void fl_open_callback(void (*cb)(const char *))
{