We have a need to FULLY rebrand our SharePoint2013 instance. Fully designed header and footer (on every page), with custom html/js/css body (on the home page).
What's the current recommended approach for 2013? I've read Application Customizers, but heard those are more for Modern Pages and SP2016+. I've read CustomAction and JSLink, but heard those are being deprecated now.
What's Microsoft's current guidance for a FULL rebrand?