Before you open a file, the editor now checks if it isn't too big.

file.py

@@ -1,8 +1,11 @@
 #!/usr/bin/python3
+import os.path
 
 from PyQt6.QtWidgets import QFileDialog
 from editor import BitEditor
 
+MAX_FILE_SIZE = 262144  # 2^18
+
 
 class FileActions:
     def __init__(self, app):
@@ -18,6 +21,10 @@ class FileActions:
         if dialog.exec():
             for file_path in dialog.selectedFiles():
                 if not file_path in self.app.open_files:  # dont open file twice
+                    if os.path.getsize(file_path) > MAX_FILE_SIZE:
+                        self.app.utils.ftb_popup.exec()
+                        return
+
                     self.app.open_files[file_path] = File(self.app, file_path, file_path.split("/")[-1])
 
     def save_current_file(self):

utils.py

@@ -2,6 +2,7 @@
 
 import sys
 from pathlib import Path
+from PyQt6.QtCore import Qt
 from PyQt6.QtWidgets import QMessageBox
 from file import File
 
@@ -22,6 +23,15 @@ class Utils:
             QMessageBox.StandardButton.Cancel
         )
 
+        self.ftb_popup = QMessageBox()  # dialog that says that the file is too big
+        self.ftb_popup.setWindowTitle("File Too Big!")
+        self.ftb_popup.setText("The file you are trying to open is too big!")
+        self.ftb_popup.setDetailedText(
+            "I am way too lazy to make the editor capable of handling big files,\n"
+            "but you could improve the editor, if this annoys you.\n"
+            "https://teapot.informationsanarchistik.de/Wobbl/Bread_Editor"
+        )
+
     def unsaved_changes_popup(self):
         button = self.usc_popup.exec()