Firefox crashes when working with PDF files
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Crash signatures ( what's this? ): nsIFrame::GetAncestorWithView()
Older versions of the Adobe Reader plugin can cause Firefox to crash when opening or closing certain PDF files.
Adobe has released a new version of the plugin that addresses this issue. Update the plugin to the latest version by following the steps on the Adobe site.
Note: Firefox 3.6.4 and above also load plugins separately from Firefox, allowing Firefox to stay open if a plugin crashes. To make sure you are using the latest version of Firefox, see Updating Firefox.

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