I just installed updates from the past six days to my Dapper installation (with all updates applied), and the display has stopped working properly, even after restarting. Symptoms:
* Areas that are supposed to be moved from one part of the screen to another are not: dragging a window causes the window to mostly disappear, and scrolling anything (whether a Web page, or a GTK+ listbox) draws only the newly-revealed area without scrolling the rest.
* The caret is invisible in Gecko/XUL text fields, but visible in GTK+ ones.
* Panel applets, and Internet Explorer under Wine, both draw their buttons and other chrome without clearing the background underneath, for an interesting layered effect.
* Returning from gnome-screensaver results in a black screen, until I hover over the various controls in the invisible gnome-screensaver alert, whereupon they appear.
These problems combine to make development near-impossible; I can't see what I'm writing.
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