Thank you for trying out the new Find in Files experience. We're making improvements to the entire experience and would appreciate any feedback you're willing to give.
We're specifically talking about the "Find in Files" and "Replace in Files" experience that can be accessed via Ctrl+Shift+F and Ctrl+Shift+H respectively. They can also be accessed from the Edit > Find and Replace menu.
If you need to disable the new experience, use Visual Studio search to look for "Preview Features" and check "Use Previous Find in Files"