Fix #708

app/src/main/java/eu/kanade/tachiyomi/util/DiskUtil.kt

@@ -16,8 +16,11 @@ import java.security.NoSuchAlgorithmException
 object DiskUtil {
 
     fun isImage(name: String, openStream: (() -> InputStream)? = null): Boolean {
-        val contentType = URLConnection.guessContentTypeFromName(name)
-                ?: openStream?.let { findImageMime(it) }
+        val contentType = try {
+            URLConnection.guessContentTypeFromName(name)
+        } catch (e: Exception) {
+            null
+        } ?: openStream?.let { findImageMime(it) }
 
         return contentType?.startsWith("image/") ?: false
     }