diff --git a/addons/account/models/account_payment.py b/addons/account/models/account_payment.py
index 2657b8141e5..845821925f7 100644
--- a/addons/account/models/account_payment.py
+++ b/addons/account/models/account_payment.py
@@ -494,7 +494,10 @@ class account_payment(models.Model):
                     move.line_ids.remove_move_reconcile()
                 move.button_cancel()
                 move.unlink()
-            rec.state = 'cancelled'
+            rec.write({
+                'state': 'cancelled',
+                'move_name': False,
+            })
 
     @api.multi
     def unlink(self):
diff --git a/addons/document/models/ir_attachment.py b/addons/document/models/ir_attachment.py
index 2bc6aee234d..bdc4559e893 100644
--- a/addons/document/models/ir_attachment.py
+++ b/addons/document/models/ir_attachment.py
@@ -9,7 +9,7 @@ import zipfile
 from odoo import api, models
 
 _logger = logging.getLogger(__name__)
-FTYPES = ['docx', 'pptx', 'xlsx', 'opendoc', 'pdf']
+FTYPES = ['docx', 'pptx', 'xlsx', 'opendoc']
 
 def textToString(element):
     buff = u""
@@ -92,6 +92,9 @@ class IrAttachment(models.Model):
     def _index_pdf(self, bin_data):
         '''Index PDF documents'''
 
+        # extractText gives very bad results for indexing, hence we don't index PDF anymore. A
+        # better alternative is probably PDFMiner.six, but not for stable.
+        # See POC at https://github.com/odoo/odoo/pull/27568.
         buf = u""
         if bin_data.startswith(b'%PDF-'):
             f = io.BytesIO(bin_data)
diff --git a/addons/point_of_sale/wizard/pos_details.xml b/addons/point_of_sale/wizard/pos_details.xml
index 6e1eb5f5ae3..3226f42cb11 100644
--- a/addons/point_of_sale/wizard/pos_details.xml
+++ b/addons/point_of_sale/wizard/pos_details.xml
@@ -10,7 +10,7 @@
                         <field name="end_date"/>
                     </group>
                     <group>
-                        <field name="pos_config_ids" colspan="4" nolabel="1" />
+                        <field name="pos_config_ids" mode="tree" colspan="4" nolabel="1" />
                     </group>
                     <footer>
                         <button name="generate_report" string="Print" type="object" class="btn-primary"/>
diff --git a/addons/stock_dropshipping/__manifest__.py b/addons/stock_dropshipping/__manifest__.py
index 174df2b7ef2..b4ebc730c05 100644
--- a/addons/stock_dropshipping/__manifest__.py
+++ b/addons/stock_dropshipping/__manifest__.py
@@ -22,7 +22,7 @@ internal transfer document is needed.
 """,
     'website': 'https://www.odoo.com/page/warehouse',
     'depends': ['purchase', 'sale_stock'],
-    'data': ['data/stock_data.xml'],
+    'data': ['data/stock_data.xml', 'views/sale_order_views.xml'],
     'installable': True,
     'auto_install': False,
 }
diff --git a/addons/stock_dropshipping/views/sale_order_views.xml b/addons/stock_dropshipping/views/sale_order_views.xml
new file mode 100644
index 00000000000..8d684e365bf
--- /dev/null
+++ b/addons/stock_dropshipping/views/sale_order_views.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0"?>
+<odoo>
+    <data>
+        <!-- Do not forward-port in 12.0 and upper -->
+        <record id="view_order_form_inherit_sale_stock" model="ir.ui.view">
+            <field name="name">sale.order.form.sale.dropshipping</field>
+            <field name="model">sale.order</field>
+            <field name="inherit_id" ref="sale.view_order_form"/>
+            <field name="arch" type="xml">
+                <xpath expr="//page/field[@name='order_line']/form//field[@name='product_updatable']" position="after">
+                    <field name="purchase_line_ids" invisible="1"/>
+                </xpath>
+                <xpath expr="//page/field[@name='order_line']/form//field[@name='product_id']" position="attributes">
+                   <attribute name="attrs">{'readonly': ['|', ('product_updatable', '=', False), ('purchase_line_ids', '!=', [])]}</attribute>
+                </xpath>
+                <xpath expr="//page/field[@name='order_line']/tree/field[@name='product_updatable']" position="after">
+                    <field name="purchase_line_ids" invisible="1"/>
+                </xpath>
+                <xpath expr="//page/field[@name='order_line']/tree/field[@name='product_id']" position="attributes">
+                    <attribute name="attrs">{'readonly': ['|', ('product_updatable', '=', False), ('purchase_line_ids', '!=', [])]}</attribute>
+                </xpath>
+           </field>
+        </record>
+    </data>
+</odoo>