Comment 15 for bug 1576639

@JOnathanJOnes: this is already the case: unloaded tabs are being serialized on disk. There are several other factors at play that might trigger some network activity when reloading a tab though, depending on the cache policy requested by the server, and more generally the dynamic nature of the page. Static content will probably not issue any requests to the network when reloaded, whereas a highly dynamic web app will do.