Those who contributed words did so in a different age when we still thought that trying to glue our own additions onto Bethesda's language was a good idea. The contribution system was put on hold long ago, but everything it created is still available in the Legacy Dictionary. Use at own risk.

"So are the words contributed part of the fourth edition or no? And will there be like a 5th edition or 6th edition dictionary?"

All the print dictionaries are snapshots taken of former versions of the Legacy Dictionary, which contains both canon and contributions. Note that even the fourth edition is outdated these days. By default, it is unlikely there will be an update as Legacy vocabulary is no longer an official focus of the site.

So are the words contributed part of the fourth edition or no? And will there be like a 5th edition or 6th edition dictionary?