Follow the instructions below to change (or remove) the transparency of the video thumbnail image on YouTube videos.
1) Log into your App Manager and select your app.
2) Click Colors from the left-hand-side of the screen (or the middle of the screen).
3) Scroll down to the Advanced SCSS box. If there is already code in the advanced SCSS box, do not remove it. Start a new line “after” the last character in the box, then paste the above code.
/*** BEGIN: YOUTUBE CHANGE THUMBNAIL TRANSPARENCY ***/
.sprite {
background-color: rgba(255,255,255,.0);
}
/*** END: YOUTUBE CHANGE THUMBNAIL TRANSPARENCY ***/
4) Click Save.
NOTE: Edit the transparency by editing the “.0” to fit your needs. The “.0” is no transparency, and “.9” full transparency.