I found one post about my problem. It´s from May 2019:
Gutenberg space between Blocks – Weaver Support Forum (weavertheme.com)
I had for a longer time not been able to make Section Blocks getting stacked seemless on a page until I realized that it is theme related. Found it in Weaver customizer here:
Spacing, Widths, Alignment –> Content –> Block Editor Element Margins containing values for:
Margins Before Blocks (em) and Margins After Blocks (em)
Then changing them from the default 1.2 and 1.5 em to zero – both – made it work fine.
What is strange is that if I then write Custom CSS ind Weaver Admin –> Fonts & Custom it causes the margin values reset to default 1.2 em and 1.5 em no matter what kind of CSS I write or even not writing anything, just cliking the Update button!
And furthermore, if I try to style these elements by this:
#content [class^=wp-block-] {margin-bottom:2.5em;} Changing 2.5 to zero of course (as suggested by scambler in linked post from 2019) doesn´t change anything. Nor do any other attempts to style this exact element.
I had hoped to find a value for the block Section made by Getwid Butenberg Blocks plugin to style this element and use only this everytime I want stacked sections without space because the default values in customizer affects all! block on a page which means that if I change values to zero I nedd to adjust all other blocks inside the Section with the Spacer Block