Toolbar Modification Questions

Hi Stackideas Team

There are a number of items in the tool bar that I will not be using on my site and I would like to remove them.
Take for example “Pages”

I have searched the forum and gather that I can do so be editing the file here:

JoomlaFolder\components\com_easysocial\themes\elegant\toolbar\default.php

The best description i have found of how to do this is here:

https://stackideas.com/forums/remove-specific-items-from-toolbar

My question is this assuming that I achieve this will my changes be overwritten on the next update?

Or is there a way to avoid the changes/modifications being overwritten?

Further I am wondering where are the images that appear in the drop down part of the toolbar stored?

thanks in advance

Paul