diff --git a/addons/product/report/product_pricelist.py b/addons/product/report/product_pricelist.py
index e6ccde44d8e..abdb705c529 100644
--- a/addons/product/report/product_pricelist.py
+++ b/addons/product/report/product_pricelist.py
@@ -28,7 +28,8 @@ class report_product_pricelist(models.AbstractModel):
         }
 
     def _get_quantity(self, data):
-        return sorted([data['form'][key] for key in data['form'] if key.startswith('qty') and data['form'][key]])
+        form = data and data.get('form') or {}
+        return sorted([form[key] for key in form if key.startswith('qty') and form[key]])
 
     def _get_categories(self, pricelist, products, quantities):
         categ_data = []
diff --git a/addons/website_sale_comparison/static/src/js/website_sale_comparison.js b/addons/website_sale_comparison/static/src/js/website_sale_comparison.js
index a52d548cb77..45b2b60d8e6 100644
--- a/addons/website_sale_comparison/static/src/js/website_sale_comparison.js
+++ b/addons/website_sale_comparison/static/src/js/website_sale_comparison.js
@@ -1,6 +1,7 @@
 odoo.define('website_sale_comparison.comparison', function (require) {
 'use strict';
 
+var concurrency = require('web.concurrency');
 var core = require('web.core');
 var utils = require('web.utils');
 var Widget = require('web.Widget');
@@ -31,6 +32,7 @@ var ProductComparison = Widget.extend(ProductConfiguratorMixin, {
         this.product_data = {};
         this.comparelist_product_ids = JSON.parse(utils.get_cookie('comparelist_product_ids') || '[]');
         this.product_compare_limit = 4;
+        this.guard = new concurrency.Mutex();
     },
     /**
      * @override
@@ -157,6 +159,9 @@ var ProductComparison = Widget.extend(ProductConfiguratorMixin, {
      * @private
      */
     _addNewProducts: function (product_id) {
+        this.guard.exec(this._addNewProductsImpl.bind(this, product_id));
+    },
+    _addNewProductsImpl: function (product_id) {
         var self = this;
         $('.o_product_feature_panel').addClass('d-md-block');
         if (!_.contains(self.comparelist_product_ids, product_id)) {
@@ -164,8 +169,9 @@ var ProductComparison = Widget.extend(ProductConfiguratorMixin, {
             if (_.has(self.product_data, product_id)){
                 self._updateContent();
             } else {
-                self._loadProducts([product_id]).then(function () {
+                return self._loadProducts([product_id]).then(function () {
                     self._updateContent();
+                    self._updateCookie();
                 });
             }
         }
@@ -192,6 +198,9 @@ var ProductComparison = Widget.extend(ProductConfiguratorMixin, {
      * @private
      */
     _removeFromComparelist: function (e) {
+        this.guard.exec(this._removeFromComparelistImpl.bind(this, e));
+    },
+    _removeFromComparelistImpl: function (e) {
         this.comparelist_product_ids = _.without(this.comparelist_product_ids, $(e.currentTarget).data('product_product_id'));
         $(e.currentTarget).parents('.o_product_row').remove();
         this._updateCookie();
diff --git a/odoo/addons/base/data/res_currency_data.xml b/odoo/addons/base/data/res_currency_data.xml
index 02e933c3f40..3ff94812022 100644
--- a/odoo/addons/base/data/res_currency_data.xml
+++ b/odoo/addons/base/data/res_currency_data.xml
@@ -222,6 +222,7 @@
             <field name="symbol">¥</field>
             <field name="rounding">1.00</field>
             <field name="active" eval="False"/>
+            <field name="position">before</field>
             <field name="currency_unit_label">Yen</field>
             <field name="currency_subunit_label">Cen</field>
         </record>
diff --git a/odoo/addons/base/models/ir_actions.py b/odoo/addons/base/models/ir_actions.py
index 6d84e6f1381..d67a1098a51 100644
--- a/odoo/addons/base/models/ir_actions.py
+++ b/odoo/addons/base/models/ir_actions.py
@@ -248,7 +248,10 @@ class IrActionsActWindow(models.Model):
         existing = self.filtered(lambda rec: rec.id in ids)
         if len(existing) < len(self):
             # mark missing records in cache with a failed value
-            exc = MissingError(_("Record does not exist or has been deleted."))
+            exc = MissingError(
+                _("Record does not exist or has been deleted.")
+                + '\n\n({} {}, {} {})'.format(_('Records:'), (self - existing).ids[:6], _('User:'), self._uid)
+            )
             for record in (self - existing):
                 record._cache.set_failed(self._fields, exc)
         return existing
diff --git a/odoo/addons/base/models/ir_model.py b/odoo/addons/base/models/ir_model.py
index bac517908a5..a7c66ae773d 100644
--- a/odoo/addons/base/models/ir_model.py
+++ b/odoo/addons/base/models/ir_model.py
@@ -1267,6 +1267,7 @@ class IrModelAccess(models.Model):
             else:
                 msg_tail = _("Please contact your system administrator if you think this is an error.") + "\n\n(" + _("Document model") + ": %s)"
                 msg_params = (model,)
+            msg_tail += ' - ({} {}, {} {})'.format(_('Operation:'), mode, _('User:'), self._uid)
             _logger.info('Access Denied by ACLs for operation: %s, uid: %s, model: %s', mode, self._uid, model)
             msg = '%s %s' % (msg_heads[mode], msg_tail)
             raise AccessError(msg % msg_params)