[Plugin: YouTube] How to change thumbnail in text area widget

Hello,

I have one simple question: I am using YouTube widget by EmbedPlus Team and I have one video embedded in one of my enhanced text widgets. I embedded it by simply pasting the embed code of the video and adjusting the size. However, the size is too big, and thumbnail is naturally small, so the quality of the picture is very low.

Is there any way to make it look sharp? Like, some way to enlarge the size of the original thumbnail? Or could I get some another thumbnail in?

Thank you in advance.