I have experience this before when using the CuteSoft editor in the past. From my understanding, it's to do with how it's been coded and when uploading images is not the same as the 'file browser' uploader.
The only work around I have seen with this is to use the file manager, or using the text/html editor to eliminate this problem.
You will find many behavioural things involve 'gifs' and not jpgs or pngs. I don't have the development skills to explain why but I have been through this many times over, especially when working with ecommerce that uses 1 image and resizes to a 'gif' thumbnail, which, if you a transparent image, it often renders the background to be black and looks terrible.
I don't believe it's anything wrong with the module as such, but how gifs and handled by uploaders and how they are treated.
In the file manager though, it's treated as a file, not an image, so it doesn't seem to suffer the same way.
Why not use jpgs, or use the file uploader and you won't have a problem for now, and perhaps in the future it might be addressed differently.
I could be wrong here, but I can only share my own many 'dnn moments' and discovered it's not really dnn, but how code works and handles different file types differently.
Nina Meiers
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