Hmm, mit Composer 2.2.12 (2.3 soll man ja noch nicht) kommt: (nach Eingabe von “composer update --no-plugins --no-scripts --no-dev”)
Problem 1
- Root composer.json requires OXID-esales/oxideshop-ide-helper ^v3.1.2 → satisfiable by OXID-esales/oxideshop-ide-helper[v3.1.2].
- OXID-esales/oxideshop-ide-helper v3.1.2 requires composer-plugin-api ^1.1.0 → found composer-plugin-api[2.2.0] but it does not match the constraint.
Problem 2
- ocramius/package-versions[1.3.0, …, 1.5.1] require composer-plugin-api ^1.0.0 → found composer-plugin-api[2.2.0] but it does not match the constraint.
- ocramius/package-versions[1.6.0, …, 1.7.0] require composer-plugin-api ^1.1.0 → found composer-plugin-api[2.2.0] but it does not match the constraint.
- OXID-esales/oxideshop-metapackage-ce v6.2.0 requires ocramius/package-versions 1.4.2|1.5.1|1.7.0 → satisfiable by ocramius/package-versions[1.4.2, 1.5.1, 1.7.0].
- Root composer.json requires OXID-esales/oxideshop-metapackage-ce v6.2.0 → satisfiable by OXID-esales/oxideshop-metapackage-ce[v6.2.0].
Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.
Running update with --no-dev does not mean require-dev is ignored, it just means the packages will not be installed. If dev requirements are blocking the update you have to resolve those problems.
Versuch 2, danke für den Tipp rubbercut
COMPOSER_MEMORY_LIMIT=-1 composer update --ignore-platform-reqs (mit Composer 1.8.4)
Loading composer repositories with package information
Warning from https://repo.packagist.org: Support for Composer 1 is deprecated and some packages will not be available. You should upgrade to Composer 2. See Deprecating Packagist.org support for Composer 1.x
Info from https://repo.packagist.org: #StandWithUkraine
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.
COMPOSER_MEMORY_LIMIT=-1 composer update --ignore-platform-reqs (mit Composer 2.2.12)
Do you trust “ocramius/package-versions” to execute code and wish to enable it now? (writes “allow-plugins” to composer.json) [y,n,d,?] y
The “ocramius/package-versions” plugin was skipped because it requires a Plugin API version ("^1.0") that does not match your Composer installation (“2.2.0”). You may need to run composer update with the “–no-plugins” option.
OXID-esales/oxideshop-composer-plugin contains a Composer plugin which is currently not in your allow-plugins config. See Config - Composer
Do you trust “OXID-esales/oxideshop-composer-plugin” to execute code and wish to enable it now? (writes “allow-plugins” to composer.json) [y,n,d,?] y
The “OXID-esales/oxideshop-composer-plugin” plugin was skipped because it requires a Plugin API version ("^1.0") that does not match your Composer installation (“2.2.0”). You may need to run composer update with the “–no-plugins” option
OXID-esales/oxideshop-unified-namespace-generator contains a Composer plugin which is currently not in your allow-plugins config. See Config - Composer
Do you trust “OXID-esales/oxideshop-unified-namespace-generator” to execute code and wish to enable it now? (writes “allow-plugins” to composer.json) [y,n,d,?] y
The “OXID-esales/oxideshop-unified-namespace-generator” plugin was skipped because it requires a Plugin API version ("^1.1.0") that does not match your Composer installation (“2.2.0”). You may need to run composer update with the "–no-p
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 OXID-esales/oxideshop-metapackage-ce v6.2.0 → satisfiable by OXID-esales/oxideshop-metapackage-ce[v6.2.0].
- incenteev/composer-parameter-handler v2.0.0 requires symfony/yaml ~2.0 → satisfiable by symfony/yaml[2.0.4, …, v2.8.52].
- You can only install one version of a package, so only one of these can be installed: symfony/yaml[2.0.4, …, v2.8.52, v3.0.0, …, v3.4.47, v4.0.0, …, v4.4.37, v5.0.0, …, v5.4.3, v6.0.0, …, v6.1.0].
- OXID-esales/oxideshop-metapackage-ce v6.2.0 requires symfony/yaml v3.4.38 → satisfiable by symfony/yaml[v3.4.38].
- Root composer.json requires incenteev/composer-parameter-handler ~v2.0.0 → satisfiable by incenteev/composer-parameter-handler[v2.0.0].
Muss das alles so kompliziert sein? 
Hat noch jemand eine Idee? Bis 6.1.4 ging das bisher immer recht problemlos.