Drupal 8.x

I am developing a custom ckeditor plugin.
Every text format has its own configuration for plugins. I need to get the format name (Basic HTML, Full HTML , ..) in my plugin class definition.
How can i achieve this?

I'm attempting to get the deploy module working on a fresh new site:
https://www.drupal.org/project/deploy
At the point I install the MultiVersion module (a dependency of deploy), I notice that any content I have created no longer shows up in the list in /admin/content.

I attend several meetups where people sign in: they write their name, phone number ... into a paper form

this serves to both record who attended and gather up to date info

I want to support this in Drupal

attendee brings up a form
enters a few characters of his name
if the name is a known contact the form is filled
attendee checks/enters/corrects info
clicks ok
the new/updated/confirmed info is recorded along with attendance

is there a module that does something like this now?

Very new to Drupal (from ExpressionEngine) and I'm having a few issues which I hope you all can help me with.

Firstly, I can't stand how Drupal is autoformatting code submitted in the WYSIWYG editor. How can I turn this off? I don't want it to change the code after submitting in any way. I want closing div tags, indentation, etc, to be preserved where it is placed. It completely ruins the workflow when I go to edit a page and all of the code is arranged completely differently than how I format it myself.

I have made a custom block in my module.

Is there a method I can override in my block class (which extends BlockBase) to respond to block deletion? I have to delete something when my block is deleted. I can see that Entity (and Block) classes have preDelete() and postDelete() static methods as well as the delete() method itself, but I don't understand how it relates to BlockBase and its interfaces.

Dear Drupal community

I'm working on streamlining the backend of my drupal website.

I have created a custom content type Post.
This content type also contains a dropdown where you can decide if this post is a Blog or Vlog.

Now I'm looking for something to hide or make fields visible when a certain dropdown option is selected.
This because for example, a vlog article requires me to show a URL field to retrieve a YT video.