Following your guidelines https://www.advancedcustomfields.com/resources/acf_register_block/ i was able to create a new block element. But several things are not working or are mysterious:
best case is to use the new block in a whole new page. when i insert the new block in a complete new page from scratch, first i don’t see the block. JS-Console fires “NO ID!”. then i have to save the page and reload it in order to see the block. Now i see it in wp admin (gutenberg) editor and in the frontend.
when i try to insert the new block in an old page where are already several blocks, i have the same problem. BUT there is a new problem: there is absolutely no way to see the block in the frontend. no matter what i try. i have no clue why. i mean i see the block in the wp admin (gutenberg) editor. it gets somehow filtered out from the frontend?! Any explanation for that please? drives me crazy