With minibuffer-depth-indication-mode enabled, the minibuffer prompts are displayed as [n] Prompt: during recursive edits where n denotes the minibuffer depth. It does so by hooking into minibuffer-setup-hook.
With ivy-mode enabled, minibuffer-depth-indication-mode doesn't seem to have any effect. That's unfortunate because it's a nice feature for people who frequently work with recursive minibuffers.
Account for minibuffer-depth-indication-mode
* ivy.el (ivy--insert-prompt): When `minibuffer-depth-indication-mode'
is on, and `minibuffer-depth' is more than 1, prepend it to prompt.
Thanks. Let me know if you want a face for the minibuffer depth. I don't really want it, and it's a bit tricky to add.
No, no extra face needed.