Top tool bar in writer is missing

OS Ubuntu 13.04; LibreOffice - version along with 13.04, no modifications.

The topmost toolbar in Writer, which has close, minimise and maximise buttons and shows the name of the document, does not show the ‘File’, ‘edit’ ‘view’, ‘insert’, ‘format’ etc. (I think it is called the ‘menu’) for one particular file but shows for all other files. This ‘disease’ has developed just today as it was showing that menu till yesterday for that particular file also.

I will be grateful if I am told how to restore it.

What is the file type (ODT, DOCX, ODP, etc.) for the file with the problem? Does that file have macros?

The file type is docx. I do not know if there are any macros as I do not know how to generate or use them. Generally I save in odt format but this file was to be sent to a devotee of Windows so I saved in docx format.

Thanks Oweng. It worked and now I feel silly for asking it, after I saw the solution given by you.

However, I hope now I will never forget it.
Sorry that I could not acknowledge it earlier as my internet connection had failed and I could access the site and your reply just now.

Solved

Thanks for providing the additional information. I initially misread your question. It now seems like you may have inadvertently invoked Full Screen Mode (CTRL+SHIFT+J). Try that key combination to see if it restores the window title bar.