Comment 0 for bug 1922404

Tested on Laserjet 1020 but might apply to any similar printer that requires firmware loading.

HPLIP attempts to establish contact with the printer too soon after uploading the firmware, while the printer is potentially not fully initialized or ready to respond over usb. This causes udev-configure-printer and hplip to time out, resulting in the printer unable to be recognized by the system.

Inserting a delay in config_usb_printer.py right after it calls hp-firmware allows enough time for the printer to complete initializing, which fixing the issue.