I'm able to upload a pic and updated it later.
My problem now is that after uploading the old picture is shown, it is
taken from the browser cache I guess.
In my app I only cache js and css.
I've tried:
expire_page "/tabs/#{@tab.id}"
redirect_to(@tab)
But it doesn't go away until I press F5 in the browser. Then the update
picture is shown.
In case anyone is interested I've solved my problem by adding a
timestamp to the picture name. That way the picture changes name when
updated so cache is not affecting at all.