[FIX] web: fix list editable visual bugs

- Tags' text were able to overflow their cell to the right
- In-edition elements were sometimes hidden by other rows' content

addons/web/static/src/less/list_view.less

@@ -130,6 +130,14 @@
     .o_data_row.o_selected_row > .o_data_cell:not(.o_readonly_modifier) {
         position: relative;
 
+        // The in-edition elements will overflow other elements (the rows below,
+        // the content below the list view, ...). As those might be using
+        // position: relative, the in-edition elements have to define a z-index.
+        // Technically, creating a stacking context for a meaningful parent
+        // (maybe the .o_content) might be required for safety but we should
+        // consider this later if needed.
+        z-index: 1;
+
         // Field widgets override
         > .o_field_widget {
             .o-position-absolute(0, 0, auto, 0);
@@ -139,11 +147,11 @@
                 white-space: nowrap;
             }
 
-            .o_field_widget, .badge { // Many2Many tags
-                display: block;
-                float: left;
-                white-space: normal;
-                max-width: 100%; // Fix a chrome bug where badge would not break on multiple lines
+            &.o_field_many2manytags > .badge {
+                &, > .o_badge_text {
+                    white-space: normal;
+                    max-width: 100%; // Fix a chrome bug where badge would not break on multiple lines
+                }
             }
         }
         > .o_field_translate {