Sort of template rendering for microsecs inbetween pageload

Hi.
OJS 3.3.0.10 (upgraded from 3.2.1.1)

When in administratioin UI if I move from some menu items to others, a sort of splash screen is displayed for some milisecs. It also happens when clicking on View submission detalis.

It seems to me something like a template rendering interval or so. See following screenshots:

pantalla-rojo-transicion-pagina

pantalla-rojo-transicion-pagina-2

I’ve cleared both data and template caches, but the problem persists.

How could I solve this?

Thanks in advance for your help.

Regards,
Juan Ascanio