Upgrading Drupal

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After upgrading to 11.2.8 my Drupal installation can't add new content type through /admin/structure/types/add

I have this log:

TypeError: Drupal\Component\Utility\Html::escape(): Argument #1 ($text) must be of type string, null given, called in {my_site}/core/lib/Drupal/Component/Render/FormattableMarkup.php on line 238 in Drupal\Component\Utility\Html::escape() (line 433 of {my_site}/core/lib/Drupal/Component/Utility/Html.php).

Hello,

On the Status Report page, I see this message:
"Mismatched entity and/or field definitions
Store
The Enabled field needs to be updated."

This is on a large, busy Drupal Commerce site in a production environment. I know that running drush devel-entity-updates  can apply schema changes, but it’s not recommended on production because it may cause data loss or unexpected changes.

Questions:

Good morning to the Drupal friends outthere,

Today I have an issue I never had before, so I am shocked a little :--/ because I don't know where to start.

In the morning I saw that there is a Drupal 11 core update to v11.2.6 on my 11.25 install.

So I prepared my stuff, db backup, file backup and handled the upgrade via composer the same procedure as last time.

composer update drupal/core "drupal/core-*" --with-all-dependencies

I'm upgrading my Drupal site's core using Composer and want to ensure a safe, smooth process. I'm looking for the community's recommended, step-by-step command-line procedure. What's the best practice for running Composer commands, and what essential Drush commands should I use before and after to handle backups, maintenance mode, and database updates to avoid issues?

After upgrading my project to Drupal 10, I encountered a consistent issue with private files stored in nested directories. Files saved in paths like private://subdir1/subdir2/file.pdf can be uploaded and found in the file_managed table, but their URLs (generated via file_url_generator) return a 404 error when accessed.

Details: