How to scroll the "info" popup window (documentation window)?

In insert mode completion, when an item is selected in the menu it may open an additional window to show documentation for the symbol (in LSP for example). How to scroll this window without mouse?

--
--
You received this message from the "vim_use" maillist.
Do not top-post! Type your reply below the text you are replying to.
For more information, visit http://www.vim.org/maillist.php

---
You received this message because you are subscribed to the Google Groups "vim_use" group.
To unsubscribe from this group and stop receiving emails from it, send an email to vim_use+unsubscribe@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/vim_use/1dc09e4b-ea01-487f-b933-d1affb885fdbn%40googlegroups.com.