If I attempt to switch frames on an animated GIF
$imageName configure -format [list GIF -index $index]
it appears to revert to frame 0; [$imageName cget -format]
returns the empty string.
On the other hand
$imageName configure -format "GIF -index $index"
works as expected.
Is something reaching directly into the string rep that
isn't there, rather than doing Tcl_GetStringFromObj?