If there's a bug in a PD that's run via PulseView it'll show a red "Decoder reported an error" field, but no indication as to what exactly the error is. Similar things probably apply to other such error messages that are not PD related. Nowadays more info is available in the PV log window, these red error messages could probably give the user a hint to look there. Won't be possible in all cases, but in some cases it might also be possible to show a more specific error message in the red box directly as well.