Board Thread:Support Requests - Designing Your Wiki/@comment-33391139-20180519051005/@comment-24142930-20180519220516

If you want to use the second image you provided as the one that appears when no image can be detected, the code would look like this:

window.pPreview.noimage = 'https://vignette.wikia.nocookie.net/ni-tian-xie-shen-against-the-gods/images/8/89/Wiki-wordmark.png/revision/latest?cb=20180408233752';

Add the code above to your common.js page and test it out. If it works and you want it to be active for all users who visit your wiki, add the code to MediaWiki:Common.js. It will take a while for it to be approved though.

Also, if you wanted to change the color/styling of the preview box, I could try and help you with changing the CSS. You can take a look at how the link preview looks on my wiki