Drupal 8.x

Hello, I took the site drupal( 8.6.1)  a get it at home. I took the core, remove the vendor and rebuild it with composer (and dependencies) and recovered the base. In "not connected" everything is fine. And then when I log with admin/... , I have this:

I am providing below code for creating link to downloadable files and make them download on your web application:

I assume the file url has been set in url that can be encoded such as:

https://www.drupal.org?destination=file-url

/**
 * Implements hook_preprocess_HOOK().
 */
function vf_theme_preprocess_page(&$variables) {

Hi

I have many articles. Each of them have a multi-values date field.
So if I fill 2 dates, this article is publish two times in my hub.

In my view, i'm sorting by this field. At this point, everything works like a charm but when I try to display date (in the twig tmp) in each article I have always the same date for all duplicates posts.

In fact, I think it's logical because it's the same entity.

Hi everyone.

Im starting a new project where I'd like to change the CSS based on the tags added. I need to be able to use 5 to 7 tags, make some sort of calculation and then use the outcome to define the CSS for that specific content.

Any ideas?

Thanks! 

after installing drupal 8.6.1 I was added a new theme to the site and set it to be the admin theme. 

now I am unable to get to any of the admin pages. the site shows 

"The website encountered an unexpected error. Please try again later"

while the rest of the site (non admin ) functions normally. 

the apache error log shows