Subtitles are not showing in Video Control window for a script addon running on KODI OSMC

I’m building a script that requires playing a playlist within a small video window (while the side and bottom are used for pictures, labels, etc.). I defined a control of type videowindow within the WindowXML file in order to do the same.

I’m successfully able to play the playlist within this small window calling the playing in windowed mode; the playlist is composed of listitems with video files and subtitles (subtitles are set using the setSubtitles method).

However, the subtitles are visible inside the videowindow control only when using the script from Kodi 17.6 used on a Mac. On OSMC (installed on Pi, with Kodi 17.6 again), the subtitles don’t appear in the videowindow, they only appear in fullscreen which is achieved by clicking the videowindow control. My script is not intended to being used with any inputs, so I need to figure a way to make the subtitles show along with the video within the videowindow (like they do on the Mac).

I would really appreciate any kind of help that would bring me closer to showing subs in the videowindow on OSMC. I can share snippets, screenshots anything that could be helpful information.

TLDR: Cannot display subtitles in a Video Control (type videowindow) of a smaller size using Kodi 17.6 on OSMC; they only display in fullscreen when the user clicks on the video control window. However, they (subs) are visible inside videowindow on a Mac running Kodi 17.6.

Thanks for taking time to read this. Appreciate any help!