I am fairly new to Sharepoint but I have a software engineering background. I have been charged with branding our companies Sharepoint intranet. We are using Office 365 Sharepoint online. The goal is to edit the master page to have a custom Header (site navigation) and footer. But the more I read on this process, the more confused I become. Apparently, we are not supposed to edit the master page anymore, with the reason being that any customizations could break if MS updates the Sharepoint Online? Does this rule also apply to Publishing style templates or just teamsites? I guess the main question is:
What is the best workflow to have custom (global)navigation (change CSS type items), and a custom footer, for a Office 365 Sharepoint Online site?
The current top site in the site collection carries a Publishing style template. Ideally, I would want any subsites(regardless of the chosen template) to inherit the header and footer to provide consistency throughout the user experience.
Any links, workflows, or advice would be greatly appreciated!