Description:
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The warning about unblocking CHM files when using Microsoft Internet Explorer under Windows XP SP2 or later applies to Firefox as well.

Reproduce code:
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The "Download documentation" section [1] has this warning:

"If you are using Microsoft Internet Explorer under Windows XP SP2 or later and you are going to download the documentation in CHM format, you need to "unblock" the file after downloading it, by right-clicking on it and selecting the properties menu item. Then click on the 'Unblock' button (on Microsoft Vista this is done in the "security" options). Failing to do this may lead to errors in the visualization of the file, due to a Microsoft bug."

Firefox implemented these restrictions in version 3.


[1] http://www.php.net/download-docs.php

Expected result:
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If you are using Microsoft Internet Explorer or Mozilla Firefox under Windows XP SP2 or later and you are going to download the documentation in CHM format, you need to "unblock" the file after downloading it, by right-clicking on it and selecting the properties menu item. Then click on the 'Unblock' button (on Microsoft Vista this is done in the "security" options). Failing to do this may lead to errors in the visualization of the file, due to a Microsoft bug.