Chromium now follows Firefox's policy on the download attribute.

src/Menu/DownloadLink.coffee

@@ -6,19 +6,16 @@ DownloadLink =
       className: 'download-link'
       textContent: 'Download file'
 
-    <% if (type === 'userscript') { %>
-    unless chrome?
-      # Firefox places same-origin restrictions on links with the download attribute.
-      $.on a, 'click', (e) ->
-        return true if @protocol is 'blob:'
-        e.preventDefault()
-        CrossOrigin.request @href, (blob) =>
-          if blob
-            @href = URL.createObjectURL blob
-            @click()
-          else
-            new Notice 'error', "Could not download #{file.URL}", 30
-    <% } %>
+    # Specifying the filename with the download attribute only works for same-origin links.
+    $.on a, 'click', (e) ->
+      return true if @protocol is 'blob:'
+      e.preventDefault()
+      CrossOrigin.request @href, (blob) =>
+        if blob
+          @href = URL.createObjectURL blob
+          @click()
+        else
+          new Notice 'error', "Could not download #{file.URL}", 30
 
     $.event 'AddMenuEntry',
       type: 'post'