Could not find package x.x.x at any version for your minimum-stability (stable) ...

"[InvalidArgumentException] Could not find package 2.5.3 at any version for your minimum-stability (stable). Check the package spelling or your minimum-stability" is caused by use of arbitrary spacing1 such as

composer require "mediawiki/semantic-media-wiki": "2.5.3";

or

composer require mediawiki/semantic-media-wiki: "2.5.3";

where in fact

composer require mediawiki/semantic-media-wiki "~2.5";

is expected.