Have you ever needed to open your screen wider and deliberately closed the Menu, Navigation, and Bookmarks toobars? Well I did today and boy did I have to scramble to get them back! It took some Internet searching!!
I guess there are other ways to have lost those tool bars since there were a lot of others who had reported having them go missing!!
I hope this never happens to you but, should you ever find yourself in that fix here is what to do:
Press the F10 key.
That will briefly open those menu options and you can then right click on the bar and re-select those bar options!