Add test for legacy failure
Use a default of 303 instead of an exception
Merge pull request #5290 from wilsonge/patch-27

Fix minor b/c break in https://github.com/joomla/joomla-cms/pull/4292
[fix] Apply on-the-fly class aliases, even for Composer packages. Fixes #5189, fixes #5179
[fix] Postgres Search case sensitive. Fixes #3529
[fix] Fix parent selector. Fixes #4665