add webp images support

js/interface_common.js

@@ -1334,7 +1334,7 @@ function _startTorrentDownloadAndPreview(torrentId, previewContainer, isMedia) {
 function webtorrentFilePreview(file, previewContainer, isMedia) {
     if (!isMedia) {
         // try guessing by filename extension
-        isMedia = /^[^?]+\.(?:jpe?g|gif|png|mp4|webm|mp3|ogg|wav|)$/i.test(file.name)
+        isMedia = /^[^?]+\.(?:jpe?g|gif|png|webp|mp4|webm|mp3|ogg|wav|)$/i.test(file.name)
     }
 
     if (isMedia) {

js/twister_formatpost.js

@@ -885,7 +885,7 @@ function setPostImagePreview(elem, links) {
         if (!previewContainer.children().length) {
             // is there any links to images in the post?
             for (var i = 0; i < links.length; i++) {
-                if (/^[^?]+\.(?:jpe?g|gif|png)$/i.test(links[i].href)) {
+                if (/^[^?]+\.(?:jpe?g|gif|png|webp)$/i.test(links[i].href)) {
                     var url = proxyURL(links[i].href);
                     previewContainer.append($('<img src="' + url + '" class="image-preview" />'));
                 }