Theme Companion

Theme updates don't always carry over your code changes. If you, a developer, or an app customized your theme's code, those edits can be left behind — and moving them by hand is slow and risky. Theme Companion carries your customizations into the new version for you. You see what changed, keep what you want, and check the result on a draft theme before going live. It also adds ready-made sections and custom fonts. Works with supported themes.