Your requirements could not be resolved to an installable set of packages. Problem 1 - typo3/cms-composer-installers[2.0.0, ..., v2.2.0] require php >=7.0.0 <7.3 -> your php version (7.3.33) does not satisfy that requirement. - typo3/cms-composer-installers[v2.2.1, ..., v2.2.4] require composer-plugin-api ^1.0.0 -> found composer-plugin-api[2.6.0] but it does not match the constraint. - roave/security-advisories dev-master conflicts with t3g/svg-sanitizer <1.0.3 (typo3/cms-core v9.5.29 replaces t3g/svg-sanitizer *). - roave/security-advisories dev-master conflicts with typo3/cms-core <8.7.51|>=9,<9.5.42|>=10,<10.4.39|>=11,<11.5.30|>=12,<12.4.4. - typo3/cms-core[v9.5.0, ..., v9.5.14] require typo3/cms-composer-installers ^2.0 -> satisfiable by typo3/cms-composer-installers[2.0.0, ..., v2.2.4]. - Root composer.json requires roave/security-advisories dev-master -> satisfiable by roave/security-advisories[dev-master]. - Root composer.json requires typo3/cms-core ^9.5 -> satisfiable by typo3/cms-core[v9.5.0, ..., v9.5.31].