&gt;  any fundamental differences between sandboxing of every thread in chrome and what electrolysis is doing?<p>&quot;Sandboxing every thread&quot; isn&#x27;t exactly what Chrome does. Chrome provides a separate process for each browser tab. That, of course, requires more memory (since processes cannot directly share memory).<p>Firefox, on the other hand, uses a single process for the rendering for all tabs, but this process is separate from the main Firefox process. This means that the browser UI is still responsive even if one of the tabs is not responsive.<p>Of course, actual profiling may yield different results due to other factors that also affect memory usage, but <i>ceteris paribus</i>, using only two processes for <i>n</i> tabs should consume less memory than using <i>n</i> processes for <i>n</i> tabs.