[FFmpeg-user] Gif encode with alpha makes a trail

[Leonardo Zerino]

I'm using this script:

#!/bin/sh

palette="/tmp/palette.png"

filters="fps=15,scale=240:-1:flags=lanczos"

#

ffmpeg -i "$1" -vf "$filters,palettegen=" -y $palette
ffmpeg -i "$1" -i $palette -lavfi "$filters [x]; [x][1:v] paletteuse" -y
"$2"

to generate a gif from a qt animation, but very frame on it is kept in the
background.
is there a away to prevent this in the code?

the gif :

https://imgur.com/a/DmTTSr9
-- 
Leonardo Zerino
(11)98479.9777