Module development and code questions

https://www.dedrone.com/products/overview 

in first paragraph, button "WATCH A VIDEO", can someone help?

hello,

in my form, in have 2 field :

- 1, textfield, with ajax and event=>"change"

- 2, select, width ajax and event=>"change"

In the fist, when i leave the field, event fire and a trait in fonction correctly.
But in the second, i never fire the event.

What is the event when a select change ?

thank's

yonnel

Trying to get the raw xml. Help appreciated ~

I have to use the same form on the same page many time. This form allows me to select an individual from a list, within different projects.
I generate this via: $ form = \ Drupal :: formBuilder () -> getForm ...

how should I do if I need to show to a link menu based on a condition ?

This is my YML for my menu link : 

    double_vue_klesia.backuserswitch:
      title: 'Retour user précédent'
      menu_name: navigation-principale
      description: 'Switch back to your user account.'
      route_name: double_vue_klesia.backuser.switch
      weight: 1

I want to show this link only : 

Please help me find why I am not able to upload extra zip files in the listing for customers to download? In the Add a new release section, I find https://www.drupal.org/node/1068944 shows in the picture there is a 'Release Files' but I don't have this field in my form.

Please advise on what to do. 

We have Drupal 7 integration uploaded before and now would like to upload Drupal 8 and keep both in the listing. Please help me find the best approach to do this. Thansk!