Have you inserted a video into an interactive container field on Windows and when playing the video looks like this?
document.getElementById('Player').stretchToFit=true; " )
First line gets player object and sets the user interface mode. This can be full, mini, invisible or none. We set it to none to hide the controls.
Next we remove the CSS transformation which causes the stretch to scale too much otherwise. Once the transformation is gone and the HTML viewer doesn't zoom in, we can ask the player to stretch itself to fill the space.
Works well here in FileMaker Pro 18 on Windows 10. Looks like this:
If you have any questions, please do not hesitate to contact us.