To change the permalink structure of your WordPress posts to use a ".html" format, you can follow these steps:
This will change the permalink structure of your WordPress posts to use the post name followed by ".html". For example, if you have a post titled "My First Post", the permalink will be "https://yourdomain.com/my-first-post.html".
Note that changing the permalink structure can affect your website's SEO and the way your posts are shared and linked to. It's recommended to set up 301 redirects to ensure that any old links to your posts are properly redirected to the new URLs.