1. A computer program product for optimizing read/write access to a document object model in a web browser, the computer program product comprising: one or more computer readable storage devices and program instructions stored on the one or more computer readable storage devices, wherein the one or more computer readable storage devices are hardware, the program instructions comprising: program instructions to detect a number of read/write accesses to a first data structure of a document object model in a web browser by one or more web browser components, wherein the document object model defines each object on a web page, one or more attributes associated with the objects, and one or more methods that can be used to manipulate the objects, and wherein the one or more web browser components include at least one of a script engine and a render engine; program instructions to determine, based on the detected number of read/write accesses to the first data structure of the document object model and on at least a first rule that defines a data structure as a highly dynamic part, whether the first data structure is a highly dynamic part of the document object model, wherein the first rule includes determining whether the number of read/write accesses exceeds a threshold, and wherein a highly dynamic part of a document object model is a data structure that creates a bottleneck in the web browser performance due to excess processing time, wherein excess processing time is due to the highly dynamic part being accessed in excess of the threshold; responsive to determining the first data structure is a highly dynamic part of the document object model, program instructions to trigger a conversion of the first data structure to an access optimized data structure; program instructions to convert the first data structure to an access optimized data structure; program instructions to detect a presence of one or more external components, wherein the one or more external components are included in the web browser, and wherein the one or more external components are unaware of the access optimized data structure; program instructions to synchronize, the highly dynamic part and the access optimized data structure, wherein the one or more external components access the highly dynamic part of the document object model; and program instructions to reroute one or more subsequent accesses of the highly dynamic part to the access optimized data structure, wherein the one or more subsequent accesses of the highly dynamic part are made by the one or more web browser components.