This plugin places the GTM container code snippets onto your wordpress website so that you do not need to add this manually.
https://wordpress.org/plugins/duracelltomi-google-tag-manager/
Widgets · WordPress Plugins
Get access to data on 650,127 websites DuracellTomi Google Tag Manager for WordPress Customers. We know of 290,014 live websites using DuracellTomi Google Tag Manager for WordPress and an additional 360,113 sites that used DuracellTomi Google Tag Manager for WordPress historically and 83,583 websites in the United States.
Get a list of 650,127 websites using DuracellTomi Google Tag Manager for WordPress which includes location information, hosting data, contact details, 290,014 currently live websites and an additional 437,081 domains that redirect to sites in this list. 360,113 sites that used this technology previouslyand 83,583 websites in the United States currently using DuracellTomi Google Tag Manager for WordPress.
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