diff --git a/addons/web/static/src/css/base.css b/addons/web/static/src/css/base.css
index 9492c53aac27677aa0d9f0765d0223b5a229cc65..b6859e7592e278d6790df0d0fb352bfa87aba6b1 100644
--- a/addons/web/static/src/css/base.css
+++ b/addons/web/static/src/css/base.css
@@ -2544,7 +2544,7 @@
 .openerp .oe_form_field_one2many > .oe_view_manager .oe_view_manager_view_list, .openerp .oe_form_field_many2many > .oe_view_manager .oe_view_manager_view_list {
   min-height: 132px;
 }
-.openerp .oe_form_field_one2many .oe_form_field_one2many_list_row_add, .openerp .oe_form_field_many2many .oe_form_field_one2many_list_row_add {
+.openerp .oe_form_field_one2many .oe_form_field_one2many_list_row_add, .openerp .oe_form_field_one2many .oe_form_field_many2many_list_row_add, .openerp .oe_form_field_many2many .oe_form_field_one2many_list_row_add, .openerp .oe_form_field_many2many .oe_form_field_many2many_list_row_add {
   font-weight: bold;
 }
 .openerp .oe_form_field_one2many .oe_list_content > thead, .openerp .oe_form_field_many2many .oe_list_content > thead {
diff --git a/addons/web/static/src/css/base.sass b/addons/web/static/src/css/base.sass
index 9897a99fe3d521c7f126b1c538af4c6472a980fe..5ca3ee7ac1b1487637d3733b1c4dd39e43c91452 100644
--- a/addons/web/static/src/css/base.sass
+++ b/addons/web/static/src/css/base.sass
@@ -2067,7 +2067,7 @@ $sheet-padding: 16px
             .oe_view_manager_view_list
                 min-height: 132px
 
-        .oe_form_field_one2many_list_row_add
+        .oe_form_field_one2many_list_row_add,.oe_form_field_many2many_list_row_add
             font-weight: bold
         .oe_list_content
             > thead