This disclosure is directed to methods and systems for managing rendering of a web page in a browser. A client operated by a user may execute code within a first fragment of a web page as the first fragment is presented to the user. The code may be injected into the first fragment by an intermediary between the client and a server of the web page. The intermediary may have split the web page into the first fragment and a plurality of fragments, and may have modified a default rendering characteristic for each of the plurality of fragments. Each of the modified rendering characteristic may include a trigger and action for rendering of a corresponding fragment. The executing code may dynamically detect a trigger for rendering of a second fragment from the plurality of fragments. The executing code may initiate a corresponding action for rendering of the second fragment.