A useful enhancement for the ace:tabSet and ace:tabPane would be to support an optional "clientCache" configuration on the tabPane component that would be used when the tabSet was in 'clientSide=false' mode. In this mode, as each tab is selected its tabPane contents are normally rendered on the server and updated on the client, providing a fully dynamic tabSet with only a single tabPane actually being rendered to the client at one time.

By specifying the new 'clientCache=true' attribute on a particular tabPane, once that tabPane had initially been rendered (by being selected), it would remain rendered on the client and subsequent selections of the same tab would not result in its contents being updated by the server. However, tab selection events (and the selected index being updated) would still occur on the server as usual, allowing the application the opportunity to be notified of the tab's selection, etc.

Putting this attribute on the tabPane instead of the tabSet would provide additional flexibility in cases where this behaviour is only desired on specific tabs. As a convenience, the same attribute could be provided on the tabSet itself to enable setting for all tabs, subject to being overridden by the tabPane's own attribute setting if defined.