I don't understand you. Do you mean to open a notebook? This is not a way to go! Opening a note in order to see the notebook's name is also not acceptable at all. Sorting by notebook is also not suitable.
God, this is the most viable meta-information of a note! For me it is way more important than the last edit date, not to mention the size of the note. The notebook name must be accessible in the All Notes list, immediately and without any additional actions, no discussion!
I cannot think of a better way to use the phone screen space!
"My notebook | 30/03/2017 | 1 KB" is just an example of where it could be placed - in that green metadata line.
The note's size is an optional metadata, I hope you knew that.. *****, there is an option to show the note's size, but no option to show the notebook!!
I am surprised that you don't see the significance and importance of this improvement!
If you have three different directories (say, Project A, Project B and Project C) with many files inside on your computer for three different projects
including File_1.txt (in Project B ), File_2.txt (in Project A) and File_3.txt (in Project C),
how do you intend to choose the right file immediately just from a list of three files (File_1.txt, File_2.txt and File_3.txt) ???
It is the folder (and notebook) structure that helps to organize and to distinguish them!
(along with tags, but tags are different story - you can assign multiple tags to a note and they are not compulsory. Don't mess them up! Tags area tags and notebooks are notebooks. They should both be visible!)
That's it. It is absolutely necessary to make the notebook name visible!!!