cannot download/enable calendar plugin via composer (v2.3.5) / update installation howto in README.md

[chaos-prevails]

Hello,

I know in an (in the meantime solved) issue this issue was mentioned as well, and it should work. However, I still don't get it to work.

My composer.json is:

{
    "name": "roundcube/roundcubemail",
    "description": "The Roundcube Webmail suite",
    "license": "GPL-3.0+",
    "repositories": {
        "0": {
            "type": "composer",
            "url": "https://plugins.roundcube.net"
        },
        "calendar": {
            "type": "vcs",
            "url": "https://github.com/JodliDev/calendar"
        },
        "libcalendaring": {
            "type": "vcs",
            "url": "https://github.com/JodliDev/libcalendaring",
            "minimum-stability": "dev"
        }
    },
    "require": {
        "php": ">=5.5.0",
        "pear/pear-core-minimal": "~1.10.1",
        "pear/auth_sasl": "~1.1.0",
        "pear/net_idna2": "~0.2.0",
        "pear/mail_mime": "~1.10.0",
        "pear/net_smtp": "~1.10.0",
        "pear/crypt_gpg": "~1.6.3",
        "pear/net_sieve": "~1.4.5",
        "roundcube/plugin-installer": ">=0.2.0",
        "masterminds/html5": "~2.7.0",
        "endroid/qr-code": "~1.6.5",
        "kolab/net_ldap3": "~1.1.1",
        "roundcube/rtf-html-php": "~2.1",
        "guzzlehttp/guzzle": "^6.5.5",
        "kolab/libkolab": ">=3.4.0",
        "sabre/vobject": "^4.0.0",
        "sabre/dav": ">=4.1.5",
        "jodlidev/libcalendaring": "dev-master",
        "roundcube/carddav": "^4.3"
    },
    "require-dev": {
        "phpunit/phpunit": "^4.8.36 || ^5.7.21"
    },
    "suggest": {
        "mkopinsky/zxcvbn-php": "^4.4.2 required for Zxcvbn password strength driver"
    },
    "config": {
        "home": "/opt/www/roundcubemail/.composer",
        "data-dir": "/opt/www/roundcubemail/.composer",
        "cache-dir": "/opt/www/roundcubemail/.composer/cache",
        "allow-plugins": {
            "roundcube/plugin-installer": true
        }
    },
    "minimum-stability": "dev"
}

I could add all config, and required plugins via composer (e.g. also jodlidev/libcalendaring via composer.phar require jodlidev/libcalendaring "dev-master"

However, if I try the same for jodlidev/calendar (composer.phar require jodlidev/calendar "dev-master"), I get

www-data@mail:/opt/www/roundcubemail$ composer.phar require jodlidev/calendar "dev-master"
./composer.json has been updated
Running composer update jodlidev/calendar
Loading composer repositories with package information
Info from https://repo.packagist.org: #StandWithUkraine
Updating dependencies
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Root composer.json requires jodlidev/calendar, it could not be found in any version, there may be a typo in the package name.

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see <https://getcomposer.org/doc/04-schema.md#minimum-stability> for more details.
 - It's a private package and you forgot to add a custom repository to find it

Read <https://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.

Installation failed, reverting ./composer.json and ./composer.lock to their original content.

www-data@mail:/opt/www/roundcubemail$ composer.phar require jodlidev/calendar 

In PackageDiscoveryTrait.php line 375:

  Could not find a matching version of package jodlidev/calendar. Check the package spelling, your version constraint and that the package is available in a stability which matches your minimum-stability (dev).  

require [--dev] [--dry-run] [--prefer-source] [--prefer-dist] [--prefer-install PREFER-INSTALL] [--fixed] [--no-suggest] [--no-progress] [--no-update] [--no-install] [--update-no-dev] [-w|--update-with-dependencies] [-W|--update-with-all-dependencies] [--with-dependencies] [--with-all-dependencies] [--ignore-platform-req IGNORE-PLATFORM-REQ] [--ignore-platform-reqs] [--prefer-stable] [--prefer-lowest] [--sort-packages] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--apcu-autoloader-prefix APCU-AUTOLOADER-PREFIX] [--] [<packages>...]

so for the moment, I have to manually download the master.zip file, and deploy it in ./plugins/

I also think that the installation howto is not correct? AFAIK there is no need for kolab/calendar, and beside adding the repositories, it would need to add the requirements for jodlidev/libcalendaring and jodlidev/calendar, right?