Web request produced exception (Url: ) in 'DiscordMessages v2.1.2' plugin (UriFormatException: Invalid URI: The URI is empty.) at System.Uri.CreateThis (System.String uri, System.Boolean dontEscape, System.UriKind uriKind) [0x0007b] in :0 at System.Uri..ctor (System.String uriString) [0x00014] in :0 at System.Net.WebRequest.Create (System.String requestUriString) [0x0000e] in :0 at Oxide.Core.Libraries.WebRequests+WebRequest.Start () [0x00014] in :0

That is because one of the webhook url's in the config is empty and you have that feature enabled.