After upgrading to Magento 2, are you getting a "Fatal error: Uncaught Error: Call to a member function getSectionNames()" message? To get the whole solution, see this blog post.
Every year, Adobe updates its products, resolving bugs and introducing new functionality to the Magento platform. Minor updates and patches are released in between the major improvements, which occur every six to twelve months. These updates include brand-new functions and features, well-known bug fixes, and security upgrades.
These new feature introductions might occasionally cause issues due to conflicts with the store's already-existing customizations. The "Fatal error: Uncaught Error: Call to a member function getSectionNames()" is one such problem that appears after updating Magento's version.
The identical problem just came up when I upgraded a client's store from Magento 2.3.3 to 2.4.5. Further research revealed the issue's primary cause.
For more information, Visit: https://meetanshi.com/blog/uncaught-error-call-to-a-member-function-getsectionnames/