I cannot find any errors in the blocks. There aren't any warning triangles within the blocks or "abandoned" pieces of blocks, either.
When I press on the up/down arrows at the "Show/Hide Warnings" element, it just jumps into an empty area without any code at all.
The app works as intended. There are just those annoying 6s on the left side...
loose blocks hidden behind other blocks?
empty sockets in blocks somewhere ?
Try right click on blocks editor the select Clean up blocks (this will put all your blocks in a vertical display) - you should be able to find the problem blocks then.
I found them. Rearranging the blocks with the right click has arranged the loose blocks so neatly that they looked like a procedure... Sorry for the stupid question ...