Slowparse, a friendlier HTML5 parser.

Slowparse is an experimental HTML5 parser that yields friendlier errors than most other parsers, using localisable strings. The fields below let you test Slowparse by writing HTML in the left panel, which will either render in the right panel if correct, or will show the base error detected in the middle panel with the error rendered in a friendlier, human-readable form on the right.