That's an interesting idea - a flag to dsm('', '', $persistent) that would a) watchdog() the message, b) display the text on every page with a "hide message" that the user could manually click on to hide it later. Persistent messages would be logged in the watchdog log.

The potential problem with this, however, is to /whom/ the message is persistent. If five people are admins, and one enables a certain module, dsm() would traditionally persist the message only to the enabler (since they're all stored in $_SESSION, of course).

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