Ableton Plugin MIDI issues since update 2.6?

Since I updated to 2.6, the MIDI output of the plugin appears to have stopped working in Ableton. Inside the plugin I can see that it’s sending MIDI notes and CC out of the plugin, but this is not showing up on the Plugin MIDI OUT channel in Ableton.

If I select IAC Driver as the plugin MIDI output then MIDI appears via the IAC MIDI input in Ableton but if I select Plugin-MIDI as the output, I get nothing showing up on the Plugin MIDI OUT track in Ableton.

Anyone having the same issue or have any ideas what might be going wrong?

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