Before discovering this forum, I tried to create rotating, linked header images using the WordPress Responsive Image Header Slider Plugin. It didn't work to my satisfaction (or I couldn't figure out how to get it to work), so I deactivated and deleted the plugin and the code snippets that it had suggested inserting (shortcode).

Unfortunately, I am left with a different code snippet in the header area: body class="home blog logged-in admin-bar no-customize-support" > which I don't know where it came from or how to get rid of it.

Any suggestions would be appreciated.

have you tried disabling ALL your plugins to see if there is a conflict?
what is the url?
go to ATO->export/import and export your settings then attach them to a reply (use the paper clip icon)

The URL is www.prineb.org

I haven't tried disabling all plugins yet.

Thanks for any help.

I haven't tried disabling all plugins yet.

well let me know what happens when you do disable them ALL.

I deactivated all the plugins and there was no change to the code snippet found at the top of the website.

Odd, with your settings I have no issue. You haven't modified any of the theme code by any chance?