HamApps Support (VK3AMA)
JTDX is not compatible with JTAlert 2.13.0 with respect to Callsign highlighting instructions sent by JTAlert.
JTDX users need to turn off the "Color Band Activity Callsign with alert colors" checkbox in the Settings, "Applications -> WSJT-X" section.
The problem is that JTDX developers have chosen to remove some of the standard WSJT-X UDP API commands, Callsign highlighting is one of the commands. Each UDP command has a unique identifying number (#13 in this case), so why JTDX is breaking when it receives a command it doesn't support is unknown, it should just ignore/dump unsupported UDP command packets, IMO.
The next JTAlert release explicitly prevents sending the command to JTDX ignoring the state of this setting when using JTDX.
de Laurie VK3AMA