modules/gui/macosx/library/video-library/VLCLibraryVideoCollectionViewContainerView.m

@@ -145,6 +145,7 @@
     _collectionViewLayout.scrollDirection = _groupDescriptor.isHorizontalBarCollectionView ?
                                             NSCollectionViewScrollDirectionHorizontal :
                                             NSCollectionViewScrollDirectionVertical;
+    _scrollView.scrollSelf = _groupDescriptor.isHorizontalBarCollectionView;
 }
 
 - (void)setVideoGroup:(VLCLibraryVideoGroup)group
@@ -159,7 +160,7 @@
 
 - (void)collectionViewFrameChanged:(NSNotification *)notification
 {
-    if (notification.object != self) {
+    if ((NSCollectionView *)notification.object != _collectionView) {
         return;
     }
 
@@ -172,28 +173,40 @@
 
 - (NSSize)intrinsicContentSize
 {
-    NSSize collectionViewContentSize = _collectionViewLayout.collectionViewContentSize;
-    NSEdgeInsets scrollViewInsets = _collectionView.enclosingScrollView.contentInsets;
-    NSEdgeInsets collectionViewLayoutInset = _collectionViewLayout.sectionInset;
-    CGFloat insetsHeight = scrollViewInsets.top +
-                           scrollViewInsets.bottom +
-                           collectionViewLayoutInset.top +
-                           collectionViewLayoutInset.bottom +
-                           15; // Account for the scrollbar size
-
-    if (collectionViewContentSize.height == 0 || _groupDescriptor.isHorizontalBarCollectionView) {
-        CGFloat fallback = _collectionViewLayout.itemSize.height + insetsHeight;
-
-        if (fallback <= 0) {
-            NSLog(@"Unable to provide reasonable fallback or accurate rowheight -- providing rough rowheight");
-            fallback = 400;
-        }
-
-        return NSMakeSize(fallback, fallback);
+    const NSSize collectionViewContentSize = _collectionViewLayout.collectionViewContentSize;
+    const NSEdgeInsets scrollViewInsets = _collectionView.enclosingScrollView.contentInsets;
+    const NSEdgeInsets collectionViewLayoutInset = _collectionViewLayout.sectionInset;
+    const CGFloat insetsHeight = scrollViewInsets.top +
+                                 scrollViewInsets.bottom +
+                                 collectionViewLayoutInset.top +
+                                 collectionViewLayoutInset.bottom;
+    const CGFloat width = scrollViewInsets.left +
+                          scrollViewInsets.right +
+                          collectionViewLayoutInset.left +
+                          collectionViewLayoutInset.right +
+                          self.frame.size.width;
+
+    if (collectionViewContentSize.height == 0) {
+        // If we don't return a size larger than 0 then we run into issues with the collection
+        // view layout not trying to properly calculate its size. So let's return something
+        NSLog(@"Unable to provide accurate height for container -- providing rough size");
+        const CGFloat roughValue = _collectionViewLayout.itemSize.height + insetsHeight;
+        return NSMakeSize(width, roughValue);
     }
 
-    collectionViewContentSize.height += insetsHeight;
-    return collectionViewContentSize;
+    if (_groupDescriptor.isHorizontalBarCollectionView) {
+        const CGFloat viewHeight = _collectionViewLayout.itemSize.height +
+                                   insetsHeight +
+                                   15; // Account for horizontal scrollbar
+        return NSMakeSize(width, viewHeight);
+    }
+
+    // HACK: At very specific widths of the container, the full height containers
+    // can have a bug where the top rows of the collection view are not displayed
+    // at all. By reducing the height of the container to below the height of the
+    // collection view contents we can eliminate this, so we reduce the height
+    // just enough to not be noticeable but enough for the bug to not manifest
+    return NSMakeSize(width, collectionViewContentSize.height - 15);
 }
 
 @end

modules/gui/macosx/views/VLCSubScrollView.h

@@ -31,6 +31,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (readwrite, assign) NSScrollView *parentScrollView;
 @property (readwrite, assign) BOOL scrollParentY;
 @property (readwrite, assign) BOOL scrollParentX;
+@property (readwrite, assign) BOOL scrollSelf;
 
 // Scroll views containing collection views can disobey hasVerticalScroller -> NO.
 // This lets us forcefully override this behaviour

modules/gui/macosx/views/VLCSubScrollView.m

@@ -32,6 +32,7 @@
     if(self) {
         _scrollParentX = NO;
         _scrollParentY = NO;
+        _scrollSelf = YES;
     }
 
     return self;
@@ -39,6 +40,11 @@
 
 - (void)scrollWheel:(NSEvent *)event
 {
+    if (!_scrollSelf) {
+        [_parentScrollView scrollWheel:event];
+        return;
+    }
+
     [super scrollWheel:event];
 
     if(_parentScrollView == nil || (!_scrollParentX && !_scrollParentY)) {