bfcache doesn't disable blink timers. I'm not sure how much of a problem this is, but could we have issues with the cached viewmanager trying to paint to the same device context as the currently-showing viewmanager? I'm not really too clear on the device context thing and how it works... So if this is not an issue, feel free to mark invalid or something.

I'm not clear on what you mean by this -- PresShell::Freeze() calls nsCaret::SetCaretVisible(PR_FALSE), which calls StopBlinking(), which calls KillTimer().

I mean the text-decoration:blink timer. See http://lxr.mozilla.org/seamonkey/source/layout/generic/nsTextFrame.cpp#261 etc.

Painting is totally suppressed on cached pages, so I don't think this can cause a problem. Marking INVALID as you suggested.