BUG #18563: Where is tha "FIRST" aggregate function??

The following bug has been logged on the website:

Bug reference:      18563
Logged by:          Iuri Tomazini
Email address:      iuritomazini.dev@gmail.com
PostgreSQL version: 16.0
Operating system:   pgAdmin 4
Description:        

PostagrSQL do not have a "FIRST" aggraregate function and it is a huge
mistake. All other good database has this and some of them are automatic,
such as MySQL. Take a fast search and discover that this kind of topic is
commonly find in internet (example: stackoverflow site). I am migrating for
other database, bacause of the dificulty to get a similar resource to
substitute the "FIRST" in PostgreSQL and I hope you can recognize this bad
error and implement something to suppply this lack. Good bye!