Issue #2578485 by Mile23, mayeco, TamCalderwood, alduya, Gravypower, Andy_D, alexpott, slde_rorschach: Composer::preAutoloadDump fails with no specified classmap

Issue #2652138 by phenaproxima, mondrake, nabiyllin, Gravypower, alexpott, Wim Leers, claudiu.cristea: Image styles do not play nicely with SVGs