When I selected a document in a subsite , I had the option "new document or drag file". suddenly this is changed to a menu ' new upload sync edit share". How can i change this ?
This is a recent Office365 improvement by Microsoft, you can still drag and drop files there.
"Now there are 5 more buttons. The upload and Synchronize buttons are always enabled since they apply to the whole document library. The Edit, Manage and Share button are only enabled when you select a document. The functionality to drag and drop a document in the library is still available. So there is no new functionality, but the options for edit, manage and share where some clicks away in the "…" item menu. This makes working with documents a little bit easier, and that's what it is all about. Getting work done!!"