What's new in the WebKitGTK+ 2.21.92 release?
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  - Add new API to inject/register user content in isolated worlds.
  - Add more API to JSCException to handle column number, convert exception to string, get the exception backtrace,
    create exceptions with a custom error name and report exception message with full details.
  - Fix excessive CPU usage when getting the process memory footprint.
  - Fix several crashes and rendering issues.
  - Translation updates: Polish