Which chat to choose for user support (helpdesk)?

Question

css

Good afternoon!
The requirements are roughly as follows.
There are users of the online service (all registered), if the user has a question or problem, he goes to the "Chat with technical support" page and writes a question. The first free operator answers him.
Good examples: amoCRM support, Tochka bank support.
Important:
- so that the chat can open on a separate page, and not just in the corner of the screen
- so that the chat can pick up user authorization (via API or something else), so that the user does not have to create a separate account or introduce himself to communicate with technical support.
- the ability to work with several operators
- (optional, but desirable) maintaining a ticket system.
Other support channels (E-mail, instant messengers, etc.) are possible, but secondary. The scenario should be as simple as possible: a person works with a web application, something is not clear to him, he immediately asks, he is answered, he works further.
If anyone uses a similar system, please tell me. I saw similar questions, but there in the answers some of the services are not suitable, and some are generally dead.

Answer 1

The reasons are described in the comments to CSS.

Answer 2

mibew ( https://mibew.org/ru/demo2 ) is a free open-source application for online consultation. The script can be downloaded and installed on your hosting by connecting the button to the site. The source code is open and can be modified to suit your needs, and the appearance is changed to suit your design.