The current Android regexp (^[a-z]://.?$) (https://github.com/apache/cordova-plugin-inappbrowser/blob/master/src/android/InAppBrowser.java#L1115) does not allow schemes like d2d or develop+d2d.

According to RFC 3986 (quoting) "Scheme names consist of a sequence of characters beginning with a letter and followed by any combination of letters, digits, plus ("+"), period ("."), or hyphen ("-")" (https://tools.ietf.org/html/rfc3986#section-3.1)

The regexp should be expanded to allow numbers, plus, periods and hyphens.