Ubuntu file browser does not show hidden files and folders by default,only the files and the folders the user has access to.But there is a key combination can show the hidden files and folders,and a way to make it show hidden files and folders by default.
Open up file browser and you will see something like following screen
just hit Ctrl+H at this window,all the hidden files and folders will be shown to you,press the key combination again to hidden them.
To make this be the default setting when open up file folder,go to Edit–>Preferences
tick Show hidden and backup files,then hidden files will be shown by default.