Post installation

Hi, this line of code

$active_theme = \Drupal::service('theme.manager')->getActiveTheme()->getName();

returns the name of the active theme
How do I know in addition to 'theme.manager' (\Drupal::service('theme.manager'))
what other index can I call up ?
I went to drupal api page and search for Drupal::service, it returns me the page  

public static function Drupal::service

But it doesn't bring back the list of indexes I can use

Hi All, any input on how to address this is highly appreciated. When running any batch process under D7 i am getting this error message:

I have an entity reference field that needs to be wrapped in a div, but it appears divs are now being stripped out. span and p tags are fine.

Is this a bug or by design?

Edit: Clarification - the divs appear to display fine within the views preview environment. But when I use the entity reference as a field in a contact storage form, the divs are all stripped out.

Hi Drupal Community,

I need a (noncustom module) solution for moving the placement of the help text of a Content-Type field group. By default, the helper text displays at the bottom of the field group, underneath all the fields in the field group.

What I would like is for that help text to be placed under the name of the field group. (See Image)

Alternatively, this could be accomplished if I could static content to the Form Display. 

It works when the user comes to the site...but after they open 3 pages the URL starts including sobfoldername in publichtml and also /web where my drupal 9 site is

so it looks like

instead of   

mysite.com/article1  they get   mysite.com/mysite/web/article1

I checked the htaccess files or cloudflare...nothing seems weird

I have an understanding of how PHP and Mysql work and was hoping to use Drupal to write web applications quickly.

I have a set of 5 categories (topic 1, topic 2, topic 3, topic 4, topic 5)

When a user registers on the site, the user can pick 1 or all of these topics.

Articles are written with these topics.

I want to know how to make sure that a post is seen only if a user has selected the topic during registration.

In a MySQL query "SELECT * FROM blog_table WHERE user_topic = [array of topic];"