Pues sí, David, es una pena no poder utilizar los bloques de Spectra en tu plugin, pero, al menos, encontré una sencilla solución con los bloques nativos.
Well, finally the problem is that you can’t use Spectra blocks to design a popup window with another plugin, even if it allows the design with Gutenberg.
So I designed the Nelio popup window with native blocks and the problem was solved.
