How to solve problem when installing extension via composer in yii2?

Question

Yii

I want to install the ElFinder extension for Yii2 via composer. Gives the following error:

Installation failed, reverting ./composer.json to its original content.

Answer 1

Installation failed, reverting ./composer.json to its original content.

This is not a mistake, the mistake was written earlier, give its text. This line says that the composer returned everything in its place, since there was an error, but which one is not clear. Somewhere above it is described, give more data.
Of the frequent problems with the composer, I can name the absence of a mandatory plugin for it:
composer-asset-plugin
is installed like this:

composer global require "fxp/composer-asset-plugin:~1.3"