Kodi RC4 – Subtitles Stopped Working

I just upgraded to Kodi 17 RC4 and I can no longer get subtitles to display. The files are .MKV with embedded subtitles. It has worked fine up to and including RC3. I have verified that subtitles are enabled. It doesn’t seem to matter which subtitle track is selected, nothing is displayed. I have not changed any settings. Is there a new setting in RC4? What is needed to help debug the problem.

Reverting back to RC3, everything works properly again.