I was able to successfully play a HTML template as an overlay, when the file is stored locally on the system.
As soon, as I host the HTML file to a webserver and play the webserver on a CasparCG layer, the background gets filled with a white color, instead of beeing transparent.
In the css-file, I set the background-color to transparent.
Does anyone have an idea?
Btw, when I play the webserver as a layer in OBS, the background is transparent.