Here is an example:
https://irrexplorer.nlnog.net/prefix/204.50.13.0/24
The /24 should be rpki invalid as the covering ROA only lists Origin AS 812 as valid for the range and longer prefixes.
Other validators agree with me :)
https://rpki.cloudflare.com/?view=validator&validateRoute=46482_204.50.13.0%2F24&prefix=204.50.13.0%2F24&prefixMatch=lspec&explorerTab=hierarchical
Otherwise, thanks for this wonderful tool !