Issue with WebM Video Transparency Rendering on ios app

I'm experiencing a persistent issue with transparent WebM videos rendered via WKWebView in an iOS Capacitor app. The videos display a black background frame, which does not occur in the web version of the app. I've tried:

Enabling experimental WKWebView features. Adjusting meta tags for inline video playback and hardware acceleration.

That's my code:

<Carousel
                        showThumbs={false}
                        showStatus={false}
                        showIndicators={true}
                        showArrows={false}
                        infiniteLoop={true}
                        autoPlay={true}
                        interval={5000} // Change slide every 5 seconds
                        onChange={(index) => {
                            if (playerRefs.current[index]) {
                                playerRefs.current[index]?.seekTo(0);
                                playerRefs.current[index]?.getInternalPlayer()?.play();
                            }
                        }}
                    >

                        {videos.map((video, index) => (

                            <div key={index} className="video-slide">

                                <ReactPlayer
                                    ref={(player) => (playerRefs.current[index] = player)}
                                    url={video.src}
                                    playing={isLoaded[index]} // Play only when video is loaded
                                    loop
                                    muted
                                    width="100%"
                                    onReady={() => handleVideoReady(index)} // Set loaded state when video is ready
                                    style={{ backgroundColor: 'transparent' }}
                                    config={{
                                        file: {
                                            attributes: {
                                                playsInline: true,
                                            },
                                        },
                                    }}
                                />

                                <p className="description">{video.description}</p>

                            </div>

                        ))}

                    </Carousel>

It is not occur in the web version of the app (testing with xCode).