Block not showing in the navigation if block is not displayed on the page

The TBM module doesn't list blocks that aren't placed in any region. To use a block in the TBM configuration (/admin/structure/tb-megamenu), that you don't want to show somewhere else on the page, place it in a Region at /admin/structure/block that is not being printed by your theme.

This is described in the Documentation here at point 2: https://www.drupal.org/docs/contributed-modules/the-better-mega-menu/how... →

You could create a new region called "Hidden Blocks for TBM" or so, and simply don't add it to your TWIG template page.html.twig. For this, just add a new region to your THEMENAME.info.yml as described here: https://www.drupal.org/docs/develop/theming-drupal/adding-regions-to-a-t... →

Then clear the cache and go to /admin/structure/block to place the block in the new region.

Doing so, the block is made available to the TBM module.

I am using same method as suggested by @meder

@DudeWeb
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