Do not use t() function for translating dynamic strings.

Wow, that is so cool, thank you indeed! I have made a quick code review and I really liked it. I will test this module as soon as I have some free time. Hope that it will be today =)

You know, I don't like only one thing: now breadcrumbs will be translatable only if user enable i18n. I'm not sure that this is a good idea. Moreover, what will happen with current translations for breadcrumbs? I use translations for breadcrumbs on one project. If I just update to a new version they will gone and users will see untranslated content. We should think about migration.

I didn't say that i18n in bad solution. It is great solution! But I am worry about simple multilanguage sites. But I agree with you - we could make this module like Views: translations only with i18n.

Migration
I insists on migration. I showed you an example with my project: if I update to a new module version all my translations will disapear and I will have to create new translations. My project contains 84 breadcrumb navigations and ~20-30k visitors daily. I think that they are won't be happy to see unknown language on the screen.

After last module updates I refactored your patch so now it is satisfies current requirements. Patch is attached.

I really don't like this code:

+++ b/path_breadcrumbs_i18n/path_breadcrumbs_i18n.module
@@ -0,0 +1,107 @@
+/**
+ * Implements hook_form_FORM_ID_alter().
+ */
+function path_breadcrumbs_i18n_form_path_breadcrumbs_ui_edit_form_alter(&$form, &$form_state) {
+  // Add submit function for PATH BREADCRUMBS EDIT form.
+  $form['#submit'][] = 'path_breadcrumbs_i18n_edit_form_submit';
+}
+
+/**
+ * Submit handler after saving path breadcrumbs.
+ *
+ * @param $form
+ * @param $form_state
+ */
+function path_breadcrumbs_i18n_edit_form_submit($form, &$form_state) {
+  $values = $form_state['values'];
+  if (isset($values['update_save']) && $values['op'] == $values['update_save']) {
+    $path_breadcrumbs = path_breadcrumbs_load_by_name($form_state['storage']['machine_name']);
+    if ($path_breadcrumbs) {
+      if ($path_breadcrumbs->translatable) {
+        i18n_string_object_update('path_breadcrumbs', $path_breadcrumbs);
+      } else {
+        i18n_string_object_remove('path_breadcrumbs', $path_breadcrumbs);
+      }
+    }
+  }
+}
+
+/**
+ * Implements hook_form_FORM_ID_alter().
+ */
+function path_breadcrumbs_i18n_form_path_breadcrumbs_ui_delete_form_alter(&$form, &$form_state) {
+  // Add submit function for before breadcrumb is deleted.
+  array_unshift($form['#submit'], 'path_breadcrumbs_i18n_delete_form_submit');
+}
+
+/**
+ * Submit handler before deleting path breadcrumbs.
+ *
+ * @param $form
+ * @param $form_state
+ */
+function path_breadcrumbs_i18n_delete_form_submit($form, &$form_state) {
+  $values = $form_state['values'];
+  if ($values['op'] == $values['submit']) {
+    $path_breadcrumbs = path_breadcrumbs_load($values['path_id']);
+    i18n_string_object_remove('path_breadcrumbs', $path_breadcrumbs);
+  }
+}

I think that it is better to provide hook_path_breadcrumbs_save() and hook_path_breadcrumbs_delete() than try to change forms behavior. Your variant is not module-friendly: other modules will not get translate features if they will save/update/delete path breadcrumbs.

Now we got next todo list:

• Refactor code to implement translations more carefully
• Add migration from older module releases

It is a really good idea to implement hooks first. I would be so happy to review patch with it :)

Oh, I'm sorry that you had to wait so long. I'm finally got some time to review this patch.

I found there some bugs, fixed them and commited it to 7.x-3.x. I hope that new 3.x branch will bring to Path breadcrumbs new features (like full token support) and performance improvements.

Your patch fix my fixes was commited at 26b8bbf.

@kalabro, thank you so much for your time. I am really appreciate that.

I know, we should write documentation about it.