Image file urls still point to http instead of https

That’s because the image (media) URL is stored as part of the record in the posts table. (Images/media are another type of post.)

You have several choices:

  1. Manually change each media URL to https. This might take a while if you have lots of pictures. Not really recommended.

  2. Use phpMyAdmin to change the value. There are several googles/bings/ducks on how to do this. But also not recommended – playing with the database can be dangerous.

  3. Use a plugin to fix things. One such is “Better Search and Replace”. It will do it all for you. Instructions are clear, and it is an established and well-supported plugin. It also has a ‘test’ mode that doesn’t do anything, but shows you what would have been done. I have used this many times.

Also, make sure that you have changed your htaccess file to force requests to use HTTPS. Your hosting place will usually have instructions on how to do this.