Gin Breadcrumb Region not showing on Entity.Canonical.Node pages

Please reconsider?

Even if Gin is admin only theme, it seems weird to have magic hidden settings that can't be accessed or edited from blocks UI.

Since breadcrumbs are assigned via system block ui, why not implement this with block visibility settings, and allow users to override if they wish?

Currently not in the scope or planned, sorry! I'm closing this again.

That being said, you could develop a small companion module which alters the behavior for breadcrumbs.

Maybe something like this?

<?php
/**
 * Implements hook_theme_registry_alter().
 *
 * This function prevents the Gin theme from processing breadcrumbs by removing
 * its preprocess callback from the theme registry. As a result, the theme will
 * no longer invoke gin_preprocess_breadcrumb().
 */
function MYMODULE_theme_registry_alter(&$theme_registry) {
  // Check if the 'breadcrumb' hook has any registered preprocess functions.
  if (isset($theme_registry['breadcrumb']['preprocess functions'])) {
    foreach ($theme_registry['breadcrumb']['preprocess functions'] as $key => $function) {
      // Identify the 'gin_preprocess_breadcrumb' function.
      if ($function === 'gin_preprocess_breadcrumb') {
        // Remove it so it won't be executed for breadcrumb rendering.
        unset($theme_registry['breadcrumb']['preprocess functions'][$key]);
      }
    }
  }
}
?>