Font Rendering Error in completion window

[knauth]

I just got coq.nvim setup with the Jedi server through the default nvim LSP. Unfortunately, it looks like there are missing characters, which appear as boxes like so:

I'm running alacritty with the Hack font, and other nerd font symbols from e.g. p10k render properly:

How can I debug this? I'd settle for just removing those characters.