Make a multi-resolution favicon.ico from a source image, using ImageMagick

Keep it Short and Simple

• RTFM: FavIcon Web Page Link Thumbnail

    convert image.png  -background white \
          \( -clone 0 -resize 16x16 -extent 16x16 \) \
          \( -clone 0 -resize 32x32 -extent 32x32 \) \
          \( -clone 0 -resize 48x48 -extent 48x48 \) \
          \( -clone 0 -resize 64x64 -extent 64x64 \) \
          -delete 0 -alpha off -colors 256 favicon.ico