Error of failed request: Badcolor (invalid Colormap parameter)

[crysman]

Hello, I'm trying to convert a ttyrecord file (output of ttyrec -u) using ttygif (1.4.0), but it crashes with Error of failed request: Badcolor (invalid Colormap parameter) after some time:

(that htop-like artefacts you see in the screenshot comes from the ttyrec since the session contains htop, too)

Any idea what might be wrong? Thanks

for-the-record: I have to execute it as WINDOWID=$(xdotool getwindowfocus) ttygif in order to avoid WINDOWID empty error.