I did a quick prototype (+Dart & Zig, see I'm not against them ;-)
- A-B - Abaqus - ABC - Actionscript - Ada - Arduino - Asciidoc - Asm - Autoit - Batch - Bibtex - C - C - Caml - CIL - Clojure - Cmake - COBOL - Coffeescript - Conf - Cpp - CS - CUDA - Cython - D-E-F - D - Dart - Diff - Docbook - Dockerfile - Erlang - F77 - Fortran - Freebasic - G-H - Gdscript - Genia - GLSL - Go - Graphviz - Groovy - Haskell - Haxe - HTML - J-L - Java - Javascript - JSON - Julia - Kotlin - Latex - Lisp - Lua - M-N-O - Makefile - Markdown - Matlab - Meson - Nim - NSIS - Objectivec - P - Pascal - Perl - PHP - PO - Powershell - Prolog - Python - R-S - R - Raku - Restructuredtext - Ruby - Rust - Scala - Sh - Smalltalk - SQL - Swift - T-V-X-Y-Z - TCL - Txt2tags - Typescript - Vala - Verilog - VHDL - XML - Yaml - Zephir - Zig
There are no filetype names starting with `IQUW` so I left those out.