Sometime (always?), when you Drag & Drop an Image from your computer to
a Workboard Task, the File is not visible to other people.
I sincerely don't remember from what moment this happened, but I'm quite
sure that this is not a new thing from Phorge.
There is an "attach" system. So we can attach the File to the Task.
So, the File inherits the visibility permissions of the Task.
So, the File is visible to persons who can see the Task.