Buttons are not displayed in categories

[mxmarchal]

Hi everyone,

I tried to add a button on my toolbox but the button don't show in it.
I don't have any errors or warnings in my console and I don't understand why a simple code don't work : <button text="button_text" callbackKey="button_callback></button>

And when I put the callback after Blockly is init, console say that button_callback doesn't exist.

Any idea ?

Thanks !
Maxence.