Plugin that allows you to insert a table of contents into your posts.
https://wordpress.org/plugins/easy-table-of-contents/
Widgets · WordPress Plugins
Get access to data on 677,732 websites that are Easy Table of Contents Customers. We know of 249,423 live websites using Easy Table of Contents and an additional 428,309 sites that used Easy Table of Contents historically and 121,346 websites in the United States.
Get a list of 677,732 websites using Easy Table of Contents which includes location information, hosting data, contact details, 249,423 currently live websites and an additional 130,835 domains that redirect to sites in this list. 428,309 sites that used this technology previouslyand 121,346 websites in the United States currently using Easy Table of Contents.
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