There’s plenty of space at the top on either side of the “logo”, in which to display the open folder’s name.
Being able to glance up at the top banner and quickly see the name of the folder we’re in would help anchor our reference within the folders’ structure - ESPECIALLY WHEN THE FOLDER STRUCTURE PANEL IS CLOSED. Adding the open folder’s name at the top would enhance at-a-glance visual clarity, which will also help a lot when the folders’ structure is deep and dense with many folders and sub-folders.
This feature would act as an excellent augmentation to the highlighted and bold name in the folder structure of the open folder.