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The name explained it
当前为
This script will force Firefox to show broken image icon when image failed loading, wether the image has alt attribute.
You can press Alt+R to reload the broken images.
這個Script會強制Firefox顯示圖片載入失敗的圖示，即使圖片有alt屬性。
按Alt+R會重新載入失敗的圖片。
Example:
Image without alt. you should see the icon by default.
Image with blank alt. By the default, you will see nothing.
Image with alt attribute. You should see the text in alt attribute.
After install this script, you will only see the broken image icon just like the first one.