From 50bf8c49195fcdf9c91c134e9ec4d8071502b4e3 Mon Sep 17 00:00:00 2001
From: Lior Halphon <LIJI32@gmail.com>
Date: Sun, 1 Aug 2021 15:11:33 +0300
Subject: [PATCH] Fixed a bug that sometimes prevented GBS files from being
 opened

---
 Cocoa/Document.m | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Cocoa/Document.m b/Cocoa/Document.m
index 64e3a21..5e3c5eb 100644
--- a/Cocoa/Document.m
+++ b/Cocoa/Document.m
@@ -902,7 +902,7 @@ static unsigned *multiplication_table_for_frequency(unsigned frequency)
 {
     GB_set_rendering_disabled(&gb, true);
     _view = nil;
-    for (NSView *view in _mainWindow.contentView.subviews) {
+    for (NSView *view in [_mainWindow.contentView.subviews copy]) {
         [view removeFromSuperview];
     }
     [[NSBundle mainBundle] loadNibNamed:@"GBS" owner:self topLevelObjects:nil];