12
As a workaround, if you are using a custom WebView, you can do these 2 things together:
Enable Javascript for the Webview (Eg: https://github.com/LatinSuD/slidetypekeyboard/blob/master/src/com/latinsud/android/slidetypekeyboard/HelpActivity.java) Like: myWebView.getSettings().setJavaScriptEnabled(true);
Then use javascript to swap images (Eg: https://github.com/LatinSuD/slidetypekeyboard/blob/master/assets/index.html)
Please note that this is not a solution for displaying GIFs, you must modify the content of the web, and convert/split GIF animations into different files (one for each frame) in any format (JPG, PNG, etc).