What changes do the app make to my store and how to completely remove it?
If you connect a Google Merchant Account to the shop, the app may have installed a verification tag to the header of theme.liquid file to handle site ownership verification and claim with Google. This is part of the standard verification process to use Google Shopping. The code snippet looks similar to the following
<!–Start Multiple Google Shopping Feeds verification–>
<meta name=”google-site-verification” content=”QoFAx7RP5t9BW8wgncz6VKCnwx8vedZDgOFqVhsAAnI” />
<!–End Multiple Google Shopping Feeds verification–>
If you decide to uninstall the app, due to the way Shopify work, permissions to edit the theme files will be removed from the app immediately. Therefore the app will not have an opportunity to remove this code snippet. Most of the time, it is ok to leave it there, it will not do any harm to your site performance. However in any cases that you want to remove it, you can follow the following steps.
1/ Go to Online Store > Themes. In the active theme section, click Actions > Edit code.
2/ Click theme.liquid on the left panel of the editor.
3/ Remove the code snippet (everything between and including the <!–Start Multiple Google Shopping Feeds verification–> and <!–End Multiple Google Shopping Feeds verification–>)
4/ Save the changes.
And that is it.