20 files declare their use of InlineFormManager in Commerce Core 8.2

BillingInformation.php in modules/checkout/src/Plugin/Commerce/CheckoutPane/BillingInformation.php

BillingProfileWidget.php in modules/order/src/Plugin/Field/FieldWidget/BillingProfileWidget.php

CouponRedemption.php in modules/promotion/src/Plugin/views/area/CouponRedemption.php

CouponRedemption.php in modules/promotion/src/Plugin/Commerce/CheckoutPane/CouponRedemption.php

CustomerProfileTestForm.php in modules/order/tests/modules/commerce_order_test/src/Form/CustomerProfileTestForm.php

NumberPatternForm.php in modules/number_pattern/src/Form/NumberPatternForm.php

PaymentAddForm.php in modules/payment/src/Form/PaymentAddForm.php

PaymentGatewayForm.php in modules/payment/src/Form/PaymentGatewayForm.php

PaymentInformation.php in modules/payment/src/Plugin/Commerce/CheckoutPane/PaymentInformation.php

PaymentMethodAddForm.php in modules/payment/src/Form/PaymentMethodAddForm.php

PaymentMethodEditForm.php in modules/payment/src/Form/PaymentMethodEditForm.php

PaymentMethodFormBase.php in modules/payment/src/PluginForm/PaymentMethodFormBase.php

PaymentOperationForm.php in modules/payment/src/Form/PaymentOperationForm.php

PaymentProcess.php in modules/payment/src/Plugin/Commerce/CheckoutPane/PaymentProcess.php

PluginSelectWidget.php in src/Plugin/Field/FieldWidget/PluginSelectWidget.php

ProductAttributeForm.php in modules/product/src/Form/ProductAttributeForm.php

ProductAttributeTranslationAddForm.php in modules/product/src/Form/ProductAttributeTranslationAddForm.php

ProductAttributeTranslationEditForm.php in modules/product/src/Form/ProductAttributeTranslationEditForm.php

SingleVariationWidget.php in modules/product/src/Plugin/Field/FieldWidget/SingleVariationWidget.php

TaxTypeForm.php in modules/tax/src/Form/TaxTypeForm.php