I think you may have to build this URI with, well... `URI` (or equivalent) rather than stringing it by hand.  I'm seeing weird behavior in even the simplest cases, e.g. `<a href="/delayed/jobs/SomeRealClass?args[]=[" foo",="" "bar"]"="">All schedules</a>`, which is  `http://localhost:5678/delayed/jobs/SomeRealClass?args[]=[`.