Here are the manual instructions to properly uninstall the MyCustomizer app from your store. This is necessary because Shopify doesn't let us clean up after a direct uninstallation from the Shopify's app list.
Some theme assets we had to upload to your store will still be there. They won't interfere with your theme, but it might affect the products that were created through our app. Delete or make these products unavailable.
If you still wish to sell the same products with your standard template, you can do so by switching the product template in your custom product's page, in Shopify admin :
Remove the assets from your theme (optional)
Click on "Edit code" from the "Actions" menu, in your online Store's theme page :
Open the templates dropdown. You will see two files containing the term "mczr". Click on those two files to open them, and at the top right, you will see a "Delete file" button. Click on that button for each opened file.
Repeat the same procedure for the third file named mczr.liquid which is further down in the snippets.
You should have deleted a total of three files :
What about other stuff that was added to the store ?
Concerning our MyCustomizer metafields, which are needed for our application to work well for your store: They are stored under our namespace and will never interfere with your website. We do not store private or sensitive data and do not use much space. They are not easily removable from your store admin interface due to Shopify limitations.
You do not have do manually remove them. The one script tag we use to display the customizer will be automatically removed. Here is Shopify's official documentation on this:
Script tags are scoped to the app that created them. When an app is uninstalled from a shop, all of the script tags that it created are automatically removed along with it.
Our webhooks will no longer call our MyCustomizer API once the MyCustomizer app is uninstalled. You do not have do manually remove them.
See the answer here for further details.
The cart template contains some code related to your app, why?
If you edited the code in your cart template by following our instructions here, it shouldn't be a problem to put back the code as it was. We do not edit the cart template upon installation, so it was a manual edition from someone who had access to your store. If you cannot or do not remember how you did it and if the instructions were originally properly followed, it should not affect your cart anyway.