Why this is true, I have no smattering of an idea......
When I put [ img ] and [ /img ] without spaces around my copied and pasted address, it would not work...no matter how many times I tried.
When I typed it all out from scratch, it worked.
Also helps to hold your left nostril closed with your right index-toe, under a full moon, and when your wife is in the mood for cooking.
QT