6 string references to 'Hidden' in Drupal 8

CommentWidget::formElement in core/modules/comment/src/Plugin/Field/FieldWidget/CommentWidget.php

Returns the form for a single field widget.

core.entity.schema.yml in core/config/schema/core.entity.schema.yml

core/config/schema/core.entity.schema.yml

DisplayPluginBase::optionsSummary in core/modules/views/src/Plugin/views/display/DisplayPluginBase.php

Provides the default summary for options in the views UI.

EntityViewDisplayEditForm::getFieldLabelOptions in core/modules/field_ui/src/Form/EntityViewDisplayEditForm.php

Returns an array of visibility options for field labels.

FieldBlock::blockForm in core/modules/layout_builder/src/Plugin/Block/FieldBlock.php

NodeComment::getValueOptions in core/modules/comment/src/Plugin/views/filter/NodeComment.php

Child classes should be used to override this function and set the 'value options', unless 'options callback' is defined as a valid function or static public method to generate these values.