Unhide Sub-Projects in Timesheets

I’d like an option to keep Sub-Projects un-hidden / un-collapsed in Timesheets. As we track most of our time against Sub-Projects it takes time to repeatedly drop down the sub-projects and it would be usefull to be able to see all time entered into all Sub-Projects in one view. At the moment you can only drop down one Project’s Sub-Project list at at time, while all the others are hidden.