As promised, filled under FB19433976

"Are you using the system-provided NSTextView, or are you writing your own custom text view using TextKit2?" I've tested both during my investigation: Custom text view - inherits NSView & using TextKit2: I'm able to reproduce the issue mentioned above (Xcode 16.4 - macOS 15.6) Custom text view - inherits NSTextView & using TextKit2: I'm able to reproduce the issue mentioned above (Xcode 16.4 - macOS 15.6) System-provided NSTextView: OK (Xcode 16.4 - macOS 15.6) It really seems to be because of what value is returned by : enumerateTextLayoutFragments(from: documentRange.endLocation, options: [.reverse, .ensuresLayout]) { layoutFragment in ... layoutFragment.layoutFragmentFrame.maxY ... } "For your own custom text view, you should be able to fix the issue by adjusting the viewport. This post provides a code snippet for that purpose. Please see if that helps." Yes indeed, I read this post and I can make a "workaround" with (OR without adjusting the viewport by ensuring a layout at appropriate time during scroll). That's why I thought it is may be intended to be that way. "The sample app you mentioned is intended to demonstrate a text rendering view with TextKit2. It is a bug that the app presents the issue, and so please file a feedback report, if you don't mind." Will do. Thanks for your quick feedback very much appreciated!

You can make it compile doing this steps: 1) Set your framework in XCode to "Do not embed" (General>Frameworks, Libraries and Embedded Content) 2) Add a "new run script phase" in "Build Phases" with: FRAMEWORK_APP_PATH="${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}" Copying FRAMEWORK to FRAMEWORK_APP_PATH find "$SRCROOT" -name '*.framework' -type d | while read -r FRAMEWORK do if [[ $FRAMEWORK == *"FAT_FRAMEWORK.framework" ]] then 		echo "Copying $FRAMEWORK into $FRAMEWORK_APP_PATH" 		cp -r $FRAMEWORK "$FRAMEWORK_APP_PATH" fi done 2. Loops through the frameworks embedded in the application and removes unused architectures. find "$FRAMEWORK_APP_PATH" -name '*.framework' -type d | while read -r FRAMEWORK do if [[ $FRAMEWORK == *"FAT_FRAMEWORK.framework" ]] then 		 		echo "Strip framework: $FRAMEWORK" 		FRAMEWORK_EXECUTABLE_NAME=$(/usr/libexec/PlistBuddy -c "Print CFBundleExecutable" "$FRAMEWORK/Info.plist") 		FRAMEWORK_EXECUTABLE_PATH="$FRAMEWORK/$FRAMEWORK_EXECUTABLE_NAME" 		echo "Executable is $FRAMEWORK_EXECUTABLE_PATH" 		EXTRACTED_ARCHS=() 		for ARCH in $ARCHS 		do 		echo "Extracting $ARCH from $FRAMEWORK_EXECUTABLE_NAME" 		lipo -extract "$ARCH" "$FRAMEWORK_EXECUTABLE_PATH" -o "$FRAMEWORK_EXECUTABLE_PATH-$ARCH" 		EXTRACTED_ARCHS+=("$FRAMEWORK_EXECUTABLE_PATH-$ARCH") 		done 		echo "Merging extracted architectures: ${ARCHS}" 		lipo -o "$FRAMEWORK_EXECUTABLE_PATH-merged" -create "${EXTRACTED_ARCHS[@]}" 		rm "${EXTRACTED_ARCHS[@]}" 		echo "Replacing original executable with thinned version" 		rm "$FRAMEWORK_EXECUTABLE_PATH" 		mv "$FRAMEWORK_EXECUTABLE_PATH-merged" "$FRAMEWORK_EXECUTABLE_PATH" 		codesign --force --sign ${EXPANDED_CODE_SIGN_IDENTITY} ${OTHER_CODE_SIGN_FLAGS:-} --preserve-metadata=identifier,entitlements $FRAMEWORK_EXECUTABLE_PATH else 		echo "Ignored strip on: $FRAMEWORK" fi done PS: Be sure to replace FAT\_FRAMEWORK by YOUR\_FRAMEWORK\_NAME (ex: ITLogin) and place it at the root of your project.