phrases - "the page elements" or "the page's elements"

Many times I see constructions like

the node's text , the node text

the node's tag, the node tag

the page elements, the page's elements

the page footer (to mean the footer of page), the page header...

I know that they are different but it seems sometimes they can be used in place of each other. for example what is the difference of

• the page elements


• the elements of page


• the page's elements

I found it awkward to repeat the page's elements if I can't use "the page elements".

Are there times that we can use both an adjective and a possessive construction for something?