Use another system class to mark invisible elements

addons/html_builder/__init__.py

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+# -*- coding: utf-8 -*-

addons/html_builder/__manifest__.py

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+# -*- coding: utf-8 -*-
+{
+    'name': "HTML Builder",
+    'summary': "Generic html builder",
+    'description': """
+    This addon contains a generic html builder application. It is designed to be
+    used by the website builder and mass mailing editor.
+    """,
+
+    'author': "Odoo",
+    'website': "https://www.odoo.com",
+
+    # Categories can be used to filter modules in modules listing
+    # Check https://github.com/odoo/odoo/blob/15.0/odoo/addons/base/data/ir_module_category_data.xml
+    # for the full list
+    'category': 'Uncategorized',
+    'version': '0.1',
+    'auto_install': True,
+
+    # any module necessary for this one to work correctly
+    'depends': ['base', 'html_editor', 'website'],
+
+    # always loaded
+    'data': [
+        # 'security/ir.model.access.csv',
+        'views/views.xml',
+    ],
+
+    'assets': {
+        'web.assets_backend': [
+            'html_builder/static/src/website_preview/**/*',
+        ],
+        # this bundle is lazy loaded when the editor is ready
+        'html_builder.assets': [
+            ('include', 'web._assets_helpers'),
+
+            'html_builder/static/src/bootstrap_overriden.scss',
+            'web/static/src/scss/pre_variables.scss',
+            'web/static/lib/bootstrap/scss/_variables.scss',
+            'web/static/lib/bootstrap/scss/_variables-dark.scss',
+            'web/static/lib/bootstrap/scss/_maps.scss',
+
+            'html_builder/static/src/**/*',
+            ('remove', 'html_builder/static/src/website_preview/**/*'),
+            ('remove', 'html_builder/static/src/website_mass_mailing/**/*'),
+        ],
+        'html_builder.inside_builder_style': [
+            ('include', 'web._assets_helpers'),
+            ('include', 'web._assets_primary_variables'),
+            'web/static/src/scss/bootstrap_overridden.scss',
+            'html_builder/static/src/**/*.inside.scss',
+        ],
+        'html_builder.iframe_add_dialog': [
+            ('include', 'web.assets_frontend'),
+            'html_builder/static/src/snippets/snippet_viewer.scss'
+        ],
+        'web.assets_unit_tests': [
+            'html_builder/static/tests/**/*',
+            ('include', 'html_builder.assets'),
+        ],
+    },
+    'license': 'LGPL-3',
+}