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They were both entered into the sidebar html through editor both before, and after the update.
Do you mean that you’ve entered the codes directly into the theme’s sidebar.php file using the WP Admin > Appearance > Editor page? If yes, then of course the changes would be gone when you update the theme, since WordPress replaces all of the theme’s files with the updated ones.
If you wish to keep your customisations when you update the theme, make sure you implement the customisations by using a child theme.