Shopify Online Store 2.0 section groups / header-footer section groups broken or not rendering in theme editor.

Several “theme editor looks wrong” bugs look alike. They do not share one fix. This page is only when Customize still opens, template body sections still load, but Online Store 2.0 Header / Footer section groups (header-group / footer-group) do not render their sections in the editor sidebar or canvas — or Add section inside that group fails. When the whole theme customizer opens blank / white or JSON templates will not load at all, open JSON templates / section groups blank customizer. When app blocks / theme app extensions never appear in the editor picker, open theme app extensions not appearing. When a Hydrogen / Oxygen headless cart is broken, open Hydrogen cart broken. When an embedded admin app paints a blank screen after install, open admin app blank after install. App embeds that never paint on the live storefront are app embed not loading. This page is only: Online Store 2.0 section groups / header-footer section groups broken or not rendering in the theme editor.

Six ordinary reasons a section group stays broken: sections/header-group.json or footer-group.json references a section type whose .liquid file was deleted in a merge; an app section type remains after the app was uninstalled; trailing commas / invalid JSON in the group file; layout/*.json dropped the header or footer group reference; you are editing a duplicate unpublished theme while the live theme still works; or you are debugging a blank customizer / missing app blocks / Hydrogen cart / admin App Bridge blank as if they were the same bug. Walk them in that order. You already pay for Shopify. You do not need another theme SaaS to prove Header and Footer sections render again.

Open Online Store → Themes → Customize on the OS 2.0 theme you actually ship. Confirm the editor chrome loads and a product / home template body still shows sections. Then open the Header and Footer groups in the left sidebar. Screenshot empty groups, missing section rows, greyed Add section, or a canvas with no header/footer blocks while the body still paints.

If Customize is entirely blank / white or no JSON template loads, leave for JSON templates / customizer blank. If only app blocks from an installed app are missing from the Add section picker, open theme app extensions not appearing. If the bug is headless Hydrogen cart, open Hydrogen cart broken. Stay here only while Header / Footer section groups fail to render inside an otherwise working theme editor.

In the theme code editor (or Git), open sections/header-group.json and sections/footer-group.json. Validate JSON. For every type in the group, confirm a matching sections/*.liquid (or section file) still exists. Remove orphan types left after an app uninstall or a bad merge. Restore missing section files from the theme’s published backup if you deleted them by accident.

Check layout/*.json still references the header and footer section groups the way Online Store 2.0 expects. Save, then reopen Customize on that same theme. Retest: Header and Footer sidebars must list sections, Add section inside the group must work, and the canvas must render header/footer blocks again. Soft note: Latch’s 72-hour install is ops wiring on the live store — not a theme rewrite product.

Checklist: (1) screenshot Customize with body sections working and Header/Footer broken, (2) validate header-group.json / footer-group.json, (3) restore or remove unknown section types, (4) confirm layout/*.json still wires the groups, (5) reopen Customize on the same theme, (6) prove Add section inside Header and Footer, (7) publish only after editor + storefront preview match, (8) if the whole customizer is blank or only app blocks are missing, switch playbooks.

Prove it: after the fix, Header and Footer groups must list their sections, the canvas must show header/footer blocks, and Add section inside the group must open the picker. If Customize is still entirely blank, open JSON templates / customizer blank. If only theme app extension blocks are missing, open theme app extensions not appearing.

Whole customizer blank / JSON templates not loading is JSON templates / section groups blank. Theme app extensions / app blocks missing from the picker is theme app extensions not appearing. Hydrogen / Oxygen cart broken is Hydrogen cart broken. Embedded admin app blank after install is admin app blank after install. None of those fix an Online Store 2.0 header-group / footer-group that will not render sections inside an otherwise working theme editor.

Finish prove Header/Footer group failure → repair group JSON / section types / layout references → editor render proof first. Only then open the related playbook that matches the remaining symptom.

Stay DIY if you can spend one afternoon on the list above: prove Header/Footer section groups fail while the editor still opens, validate header-group / footer-group JSON, restore or remove unknown section types, confirm layout references, and stop treating blank customizer / theme app extensions / Hydrogen cart / admin blank as the same bug. That is the whole playbook. No agency required. Short answers also live on the merchant FAQ. Related pages: JSON templates blank, Theme app extensions, Hydrogen cart, Admin app blank.

Pay $997 when the gap is wiring the stack you already pay for — lead capture, ops alerts, checkout-ready workflow on the live store — not when you only need a header-group JSON repair. One live store. No earnings claims, no ticket-cut promises, no recovered-revenue math. Checkout: https://whop.com/checkout/plan_jHoFkwA8EXHTD.

Buy the 72-hour install — $997HomeFAQ

Nico at Latch AI Ops · Updated 2026-09-10 · DIY-first · No earnings claims