XAMPP + MediaWiki + Composer installing extensions - php

Question

I used the Windows Setup.exe to install Composer. It now works from the command line.
I have an installation of XAMPP in C:\ that contains MediaWiki installed in the HTDOCS folder.
My goal: Install the extensions Semantic Breadcrumb Links and Semantic Extra Special Properties into MediaWiki.
The problem: Composer floods me with a bunch of nonsense downloads of vendor folders I already possess, ignoring the SBL/SESP stuff entirely.
I deleted my composer.json file in the MW root folder entirely. Then went to the command line and entered this to recreate and add to it.
composer require mediawiki/semantic-breadcrumb-links ~1.4
composer require mediawiki/semantic-extra-special-properties ~1.5
The composer.json is created with those two in it. I already have Semantic MediaWiki and it's dependencies installed. Composer Merge Plugin is in my Vendors folder and is installed according to MediaWiki.
I run this command:
composer update
And then I get slammed with a bunch of talk about composer.json being read, then not being found in a Composer folder located in my Roaming folder. Then it starts spitting out Github information. And then it proceeds to download file after file, and write them to a cache in my AppData/Local/Composer/repo folder.
All of the files written already exist inside my Vendor folder in the MediaWiki installation.
I can't find anything online about the two extensions I want to install. An example of the output:
Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.
C:\Users\Ghaleon>cd c:\xampp\htdocs\zephyr
c:\xampp\htdocs\zephyr>composer require mediawiki/semantic-extra-special-properties "~1.5" -vvv
Reading ./composer.json
Loading config file ./composer.json
Checked CA file C:\Users\Ghaleon\AppData\Local\Temp\composer-cacert-e78c8ab7b4432bd466e64bb942d988f6c0ac91cd785017e465bdc96d42fe9dd0.pem: valid
Executing command (C:\xampp\htdocs\zephyr): git branch --no-color --no-abbrev -v
Executing command (C:\xampp\htdocs\zephyr): git describe --exact-match --tags
Executing command (C:\xampp\htdocs\zephyr): git log --pretty="%H" -n1 HEAD
Executing command (C:\xampp\htdocs\zephyr): hg branch
Executing command (C:\xampp\htdocs\zephyr): fossil branch list
Executing command (C:\xampp\htdocs\zephyr): fossil tag list
Executing command (C:\xampp\htdocs\zephyr): svn info --xml
Failed to initialize global composer: Composer could not find the config file: C:/Users/Ghaleon/AppData/Roaming/Composer/composer.json
To initialize a project, please create a composer.json file as described in the getcomposer "Getting Started" section
Reading C:\xampp\htdocs\zephyr/vendor/composer/installed.json
Loading plugin Wikimedia\Composer\MergePlugin
Running 1.5.2 (2017-09-11 16:59:25) with PHP 7.1.7 on Windows NT / 6.1
./composer.json has been updated
Reading ./composer.json
Loading config file ./composer.json
Executing command (C:\xampp\htdocs\zephyr): git branch --no-color --no-abbrev -v
Executing command (C:\xampp\htdocs\zephyr): git describe --exact-match --tags
Executing command (C:\xampp\htdocs\zephyr): git log --pretty="%H" -n1 HEAD
Executing command (C:\xampp\htdocs\zephyr): hg branch
Executing command (C:\xampp\htdocs\zephyr): fossil branch list
Executing command (C:\xampp\htdocs\zephyr): fossil tag list
Executing command (C:\xampp\htdocs\zephyr): svn info --xml
Failed to initialize global composer: Composer could not find the config file: C:/Users/Ghaleon/AppData/Roaming/Composer/composer.json
To initialize a project, please create a composer.json file as described in the getcomposer "Getting Started" section
Reading C:\xampp\htdocs\zephyr/vendor/composer/installed.json
Loading plugin Wikimedia\Composer\MergePlugin_composer_tmp0
Loading composer repositories with package information
Downloading packages.json
Writing C:/Users/Ghaleon/AppData/Local/Composer/repo/https-- packagist.org/packages.json into cache
Updating dependencies (including require-dev)
Reading C:/Users/Ghaleon/AppData/Local/Composer/repo/https---packagist.org/p-pro
vider-2013.json from cache
Reading C:/Users/Ghaleon/AppData/Local/Composer/repo/https---packagist.org/p-pro
vider-2014.json from cache
Reading C:/Users/Ghaleon/AppData/Local/Composer/repo/https---packagist.org/p-pro
vider-2015.json from cache
Reading C:/Users/Ghaleon/AppData/Local/Composer/repo/https---packagist.org/p-pro
vider-2016.json from cache
Reading C:/Users/Ghaleon/AppData/Local/Composer/repo/https---packagist.org/p-pro
vider-2016-10.json from cache
Downloading provider-2017-01%24d88eddadd51717e910cd1bad29 89204217e7add9448808859860c1520b3d294d.json