Vladyslav Filonov

I dont want agents see errors in app window or console. But me as admin want to have oportunity to see logs with details (e.g. in Admin Center) in case of errors. Is there any opportunity for doing that? 

I believe that console.log is not the best idea to log errors.  Is there any other way to do that?

I have custom application on the ticket page. It makes call on external api and shows some information. But i want to log errors that happen during that call. Is there any instruments in zendesk for doing this?

Yes, end users must sign in to help center. So that is the problem. I cant see any possibility to get user's email. Is there any way to do it?

Thank you, Tipene, i'll try to clarify what i want to implement.
There is a hosting where users can rent dedicated servers, bare metal servers etc (devices it the context of that hosting). I want let people to use help center to report about issues they meet using their devices. And i want that user can choose with which device he has problem so that agent could see this information in a ticket. 
So i want to pull a list of user's devices from hosting using api and put them in ticket form in help center. For that i need somehow take user's email and make a request to api endpoint and then put user's devices in dropdown list.

Hi, Tipene.
I want to have custom form in my help center. In this form i need to have drop down list with custom parameters depending on user's email (I will use the email to make request to external API to get information for my dropdown). Is it possible to do in zendesk?

I want to add form in help center and i need it to have one dropdown list with dynamic data from different resource. Is it possible to do?

I have an app in a ticket sidebar in which i get some data from an external api. I want to show small amount of this data in ticket sidebar and full version of the data in modal window. Is there any way to pass this data from this app to modal?