Connect the Happy Bubbles device over USB to a computer and find which port it's connected to, like COM3
Get nodemcu-flasher and download the Happy Bubbles release, untar it.
In the config section, assign
Then while holding the 'flash' button on the board, press the 'reset' button too; then let go of both buttons.
Click the 'Flash' button on nodemcu-flasher.
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