Support Large Guestbooks #3609
Description
This comes up from time to time when a user with a very large guestbook wants to download it but can't. See RT 246137 for an example of a repeating request. So for now this requires us to run a database query and send the results to the user whenever they need updated info.
Please note this is separate from the bug where some guestbooks can be downloaded in FF and Safari but not Chrome ( #3581 ) . At first glance they seem the same but they are not.