"A script from ... is requesting enhanced abilities that are UNSAFE ..."

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You are getting this error message from Firefox 3.x when recording or replaying:

A script from “file://” is requesting enhanced abilities that are UNSAFE and could be used to compromise your machine or data:

Run or install software on your machine

Allow these abilities only if you trust this source to be free of viruses or malicious programs.

[ ] Remember this decision

[Allow] [Deny]

Possible cause: Missing permissions in preferences

Squish tries to add permissions to avoid this error message to the file prefs.js of the default Firefox profile. However, for several reasons this may fail.

If this occurs, please add these entries to the prefs.js file yourself.

This file reside here on Windows:


To open path, just start Windows Explorer and enter “%APPDATA%\Mozilla\Firefox\Profiles" (with the double quotes) into its path text field and press RETURN.

Please note that <profile_identifier> is a random value.

Please also note that if there is more than one folder in %APPDATA%\Mozilla\Firefox\Profiles this means that you cannot tell which of these is the default profile. To keep it simple it is suggested that you do the steps below for every prefs.js file in every profile folder then.

Open prefs.js with Notepad and add the following entries at the bottom (as new lines):

user_pref("capability.principal.codebase.Squish.granted", "UniversalXPConnect");
user_pref("capability.principal.codebase.Squish.id", "file://<SQUISH_DIR/lib/mozinit.html");

Please note that <SQUISH_DIR> must be the path to your Squish for Web installation. For example: C:\Users\myuser\squish-4.2-web-win32-20120130-1700\lib\mozinit.html.

Here is an example; note that this time the path contains the forward slash ("/"). But using the backward slash ("") is also possible:

user_pref("capability.principal.codebase.Squish.granted", "UniversalXPConnect");
user_pref("capability.principal.codebase.Squish.id", "file://C:/Users/myuser/squish-4.2-web-win32-20120130-1700/lib/mozinit.html");