Shopify SEO checklist before uninstalling an SEO app: save the fields it injects at runtime first
A lot of Shopify SEO apps don't write into your native SEO fields — they inject your meta titles, descriptions, canonical and JSON-LD (and sometimes alt-text) into the storefront at runtime, so the second you uninstall, those values vanish and your pages fall back to the theme's generic defaults. Others go the opposite way and paste code straight into your theme, which stays behind as duplicate tags after the app is gone. Either way Shopify keeps no version history of any of it, so once you've clicked uninstall there's no native way to see what the app was serving or get it back — which is why you check before, not after.
Step by step
Find out which fields the app actually owns vs. which live in Shopify natively — this is the whole risk. Open a few of your top product and collection pages, right-click > View Page Source, and read the <title>, <meta name="description">, the canonical, and any application/ld+json. Then open those SAME pages in admin under Search engine listing > Edit. If the storefront shows a title or description but the native admin field is blank, the app is injecting that value at runtime and it will disappear the moment you uninstall. Anything already sitting in the native field is yours and survives.
Export everything while the app is still installed and serving — this is your only 'before' copy. Pull a product and collection CSV with the SEO Title and SEO Description columns, and because Shopify's own export skips alt-text, a Matrixify export that includes the Image Alt Text column. Save your structured data too (run key URLs through Google's Rich Results Test) and copy your URL redirect list. Once the app is gone there's nothing left to diff against.
Move the injected values into Shopify's native fields before you uninstall, then scout for leftover code. For every field the app was rendering at runtime (from step 1), write those values back into the native Search engine listing fields — or re-import your CSV/Matrixify file — so they persist after the app leaves. Then check Online Store > Themes > Customize > App embeds and Edit code (search theme.liquid and head snippets for the app's name or comment markers) for anything it pasted in, so you know which duplicate <title>/schema blocks to strip out after uninstalling.
Capture a known-good snapshot while the app is still live, because the failures show up days later in Search Console, not the minute you uninstall. Keep a daily snapshot of every SEO field — meta titles, descriptions, alt-text, tags, handles and JSON-LD, for products AND collections — taken while everything is still rendering correctly. Then if a page goes blank or a duplicate tag appears after the uninstall, you're alerted the day it happens (with the likely cause named) and restore yesterday's known-good version in one click, instead of rebuilding from a source you no longer have.
Source: Shopify Help Center: uninstalling apps and removing leftover theme code, plus editing search engine listings; Google Search Central documentation on title links and structured data
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