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Joomla itself does not come with the Twig framework but RocketTheme's Gantry does. Are you using a Gantry-based template? If so, you might want to update both the Gantry library and your template.

I also have a suspicion that you might have taken a backup after Gantry was updated but before updating Joomla which is why restoring the backup didn't fix your problem.

The other explanation is that post-update there are new files on your site, which were not present at backup time, causing the observed issue. The reason is that restoring the backup does not delete files. It only adds or overwrites files. In nearly every use case this is what you want. However, if you are trying to roll back a version of Joomla or one of its extensions this might not work in some rare cases -- and you may have hit one of them. This is fairly easy to address:

1. Move or copy your backup archive file(s) in the site's root
2. Upload kickstart.php in the site's root as well
3. Delete the .htaccess file of your site. Note that it's hidden by default. You may have to tell your FTP client or your hosting control panel's file manager to display hidden files.
4. Delete the directories administrator, components, includes, language, layouts, libraries, modules, plugins and templates from your site's root. These are the directories where code files that could cause the problem live in.
5. Access the kickstart.php URL on your site e.g. https://www.example.com/kickstart.php if your site lives in https://www.example.com
6. Click on Start to extract the backup archive and follow the instructions on your screen to complete the restoration.