The post-processing of the mail content makes heavy use of jQuery. As a consequence, lots of nodes are kept in jQuery's internal caches. This might cause memory leaks. In order to avoid that, the UI now uses native functions to post-process the content.

Besides some internal changes, all extensions of the point io.ox/mail/detail/content need to be adjusted.

this is no longer a jQuery set but the native DOM node. It's highly recommended to use native functions like querySelectorAll() to process the content. It's ok to use jQuery on matching items (if not too many).