From my understanding if we are to host the pictures it will take up considerable space which can be costly and can slow down the running of the forum.
There are loads of free hosting sites that can be linked to and also allow people to use their pictures in other locations or just keep them for posterity.
I guess it would be possible to allow a limited storage per user and when this is exeeded you have to go back and delete old pictures, but this would then mean pictures were lost as per your original comments.
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