crashes after 4 hours

After 4 hours:
free(): invalid pointer
Backend terminated or disconnected. Fatal Python error: Aborted
file "/usr/local/lib/python3.7/dist-packaged/ST7735-0.0.3-py3.7.egg/ST7735/, line 212 in send

The actual code line is self.spi.xfer(data[start:end])
inside the def send(self,data, is_data=True, chunk_size=4096):

I’d guess that somewhere the garbage collection or release of a data buffer isn’t being done and eventually the free() fails because somewhere else the data was never allocated.
Pi 3B, Raspian Linux 10 (buster) running Pi under Thonny.