On macOS 11/12, in Emacs 28/29, any emoji (e.g. alien) makes the line with it taller than the lines with no emojis, which breaks various things across Emacs, such as avatars in telega.el (see the attachment).

To reproduce:

1. start 'emacs -Q'

2. type

> foo
> 👽 bar
> baz

3. delete the alien

Actual: the line with "bar" becomes less tall

Expected: all lines always have constant height