[Info]
Name = Start of Xfinity
Author = G. Testing
Author URL = https://github.io
Version = 2

[Start Page]
Background = Xfnfinity_intro.webm
Position = center bottom
Title Text Color = #FFFFFF
Title Text Shadow = #757575
First Frame Image = Screenshot.jpg

[Web UI Pages]
Background = Screenshot.jpg
Position = center bottom
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Thanks to this is the base file that I found in some Opera forums, I was able to run my custom theme without problems within Opera GX, but unfortunately I couldn't modify the background of the "GX Corner" tab.
Analyzing the HTML code I could see that it takes a screenshot of the video.webm file but I would like to use a different image for this browser tab.
<video disablepictureinpicture="" loop="" src="blob:https://gx-corner.opera.com/f51e828a-ae26-44ba-b018-4fd584da9746" class="svelte-xtsafi" style="">< /video>