[ADD] Contacts: Merge Contacts

closes odoo/documentation#9952

Signed-off-by: Samuel Lieber (sali) <sali@odoo.com>
Co-authored-by: pabr-odoo <pabr@odoo.com>
Co-authored-by: ksc-odoo <73958186+ksc-odoo@users.noreply.github.com>

content/applications/essentials/contacts.rst

@@ -1,3 +1,5 @@
+:show-content:
+
 ========
 Contacts
 ========
@@ -269,3 +271,8 @@ in the main contacts page, but they can still be searched for with the :guilabel
    - :doc:`Add different addresses in CRM <../sales/sales/send_quotations/different_addresses>`
    - `Odoo's eLearning Contacts tutorial
      <https://www.odoo.com/slides/slide/contacts-2527?fullscreen=1>`_
+
+.. toctree::
+   :titlesonly:
+
+   contacts/merge

content/applications/essentials/contacts/merge.rst

@@ -0,0 +1,78 @@
+==============
+Merge contacts
+==============
+
+Odoo's *Contacts* application allows user's to merge duplicate contacts, without losing any
+information in the process. This keeps the database organized, and prevents contacts from being
+contacted by more than one salesperson.
+
+.. _contacts/merge-duplicate:
+
+Merge duplicate contacts
+========================
+
+.. danger::
+   Merging is an irreversible action. Do **not** merge contacts unless absolutely certain they
+   should be combined.
+
+Navigate to the :menuselection:`Contacts app`, and select the :icon:`oi-view-list`
+:guilabel:`(list)` icon. Select two or more duplicate contacts from the list, and tick the checkbox
+(on the far-left) for the contacts that should be merged. Then, click the :icon:`fa-cog`
+:guilabel:`Actions` icon, and select :guilabel:`Merge` from the resulting drop-down menu.
+
+.. image:: merge/merge-menu.png
+   :align: center
+   :alt: The merge contacts option in the Contacts application.
+
+This opens the :guilabel:`Merge` pop-up window. From here, review the details of the contacts before
+confirming they should be merged. If any contacts in the list should **not** be merged, click the
+:icon:`fa-times` :guilabel:`(delete)` icon at the far right of the contact.
+
+.. tip::
+   Click the individual contact to open the record for that contact, and view additional
+   information.
+
+.. image:: merge/merge-window.png
+   :align: center
+   :alt: The merge pop-up window in the Contacts application.
+
+Click the :guilabel:`Destination Contact` field, and select an option from the drop-down list. This
+field defaults to the contact record that was created first in the system.
+
+After confirming the information on the pop-up window, click :guilabel:`Merge Contacts`.
+
+Deduplicate contacts
+====================
+
+After the merge is finished, a pop-up window appears confirming it is complete. This pop-up window
+also contains a :guilabel:`Deduplicate the other Contacts` button. This feature searches for
+duplicated records, based on selected criteria, and merges them automatically, or after manual
+approval.
+
+Click the :guilabel:`Deduplicate the other Contacts` button to open the :guilabel:`Deduplicate
+Contacts` pop-up window.
+
+Select one or more fields to be used in the search for duplicated records. Duplicated contacts can
+be searched, based on the following criteria:
+
+- :guilabel:`Email`
+- :guilabel:`Name`
+- :guilabel:`Is Company`
+- :guilabel:`VAT`
+- :guilabel:`Parent Company`
+
+.. note::
+   If more than one field is selected, only records that have **all** fields in common are suggested
+   as duplicates.
+
+If necessary, select criteria to be used to exclude potential duplicates from the search. Potential
+duplicates can be excluded from the search, based on the following criteria:
+
+- :guilabel:`A user associated to the contact`
+- :guilabel:`Journal Items associated to the contact`
+
+After confirming the search criteria, click either :guilabel:`Merge with Manual Check`,
+:guilabel:`Merge Automatically`, or :guilabel:`Merge Automatically all process`.
+
+If :guilabel:`Merge with Manual Check` is selected, complete the merge by following the :ref:`steps
+above <contacts/merge-duplicate>`.