Since we use FastTable in Nautilus, if you drag a Nautilus window, some icons become

transparent. (protocol icons for "private" and "initialization").

This is because fast table scales all icons to size 16@16 and this will convert

8bit forms to 16 bit forms and this may lose transparency information.

you can simulate this with

f:= Form extent: 100@ 100 depth:32.
fill := (GradientFillStyle colors: (Color wheel: 10))
origin: 50@50 ;
direction: 0@50;radial:true.
f getCanvas fillRectangle: (10@10 extent: 80@80) fillStyle: fill.
f getCanvas frameRectangle: f boundingBox width:2 color:Color blue.
(f asFormOfDepth:16) asMorph openInHand.

drawing this imagemorph works on the display screen but if you drag the

morph it becomes invisble (what you see is only the shadow).

the same behavior if you start with a form of depth 8.

converting a form of depth 32 to 8 or

8 to 32 works.

8 to 16 or 32 to 16 does not work.

There were some discussions on pharo/squeak ML (search for "fixalpha")

But I don't know where this is fixed in squeak, but it works in squeak.

I don't know exaclty what's the problem, converting the form or displaying it?

any ideas?