Web applications are becoming increasingly popular nowadays. During the development and evolution of a web application, a typical type of tasks is to change the presentation of the web application, such as correcting display errors, adding user-interface controls, or changing appearance styles. To change the presentation of a static web page, developers are able to modify the HTML text of the web page using a graphical web-page editor. However, to change the presentation of a dynamic web application, instead of using a graphical web-page editor to directly modify generated web pages, developers need to modify the code that generates the web pages. As manually performing presentation changes in dynamic web applications is tedious and error-prone, we propose a novel approach based on collaborative hybrid analysis that combines static analysis and dynamic analysis to facilitate developers to perform presentation changes in dynamic web applications. Our approach includes two parts. The first part takes as input the presentation change to be performed on a generated web page (with proper runtime information), and uses dynamic string-origin analysis to locate the source-code segment that generates the changed part of the web page. The second part checks unexpected impact of directly performing the change on the source-code segment, and asks for human intervention when unexpected impact exists. We implemented our approach for the PHP language and carried out an empirical study on 39 presentation-change tasks identified from 600 bug reports of three real-world dynamic web applications (in total more than 148 KLOC). Among the 39 tasks, our approach is able to correctly locate the place to modify in each presentation-change task and correctly perform the presentation change on the source code in more than half of the tasks.