macOS: Inconsistent result when using alt modifier key

[gmile]

In two different applications I can't get alt sequences working:

• In Postgres I get this when trying to jump words using alt+← and alt+→ keys:

  $ psql postgres
  psql (9.6.3)
  Type "help" for help.
  
  postgres=# select name, setting from pg_settings limit 10;3D3D3D3C3C3C
  

• In Elixir shell I get this:

  $ iex
  Erlang/OTP 20 [erts-9.0] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:10] [hipe] [kernel-poll:false] [dtrace]
  Interactive Elixir (1.5.0) - press Ctrl+C to exit (type h() ENTER for help)
  iex(1)> x = 1CCDD
  

There's a difference in how both programs accept sequences: 3D and 3C in one case, D in C in another.

At the same time macOS's Terminal.app handles both cases perfectly well, resulting in actual word jumps.

What should I look for to understand the difference between the two terminals handling escape sequences in order to fix this?

Edit. I do have this and this lines in my ~/.config/alacritty/alacritty.yml.

Also, weirdly, it's possible to fix alacritty behaviour in postgres by adding ~/.inputrc with the following contents:

"\e[1;3D": backward-word
"\e[1;3C": forward-word