El mòdul de dropdown_language cal actualitzar-lo al mateix temps que drupal 10. Si es vol actualitzar a drupal9:
Problem 1
- drupal/dropdown_language[dev-4.0.x, 4.0.0, ..., 4.0.3] require drupal/core ^10 -> found drupal/core[10.0.0-alpha1, ..., 10.3.x-dev] but the package is fixed to 9.5.11 (lock file version) by a partial update and that version does not match. Make sure you list it as an argument for the update command.
- drupal/dropdown_language 4.0.x-dev is an alias of drupal/dropdown_language dev-4.0.x and thus requires it to be installed too.
- Root composer.json requires drupal/dropdown_language ^4.0 -> satisfiable by drupal/dropdown_language[4.0.0, 4.0.1, 4.0.3, 4.0.x-dev (alias of dev-4.0.x)].
Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.