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"create user.js file in profile directory" to add user pref. to enable Mozilla Rich Text Editing

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  • Last reply by Center

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The ff message to me is "to protect users' information, unprivileged scripts cannot invoke the Cut, Copy and Paste commands in the Mozilla rich text editor...to enable these functions you must modify your browser preferences..." This is an online course. In the required discussion forums, and while editing my post for replies- when dragging over a sentence, then rt clk for copy/cut/paste edit options-this is when I get message to follow directions to create a user.js file inside my profiles. I have followed the "Changing the Preferences in Firefox" directions to create a user.js file(did not have one) to add the described and specific capabilities for this site (which is an .edu type site). Since didn't have a "user.js" file to open in a text editor, to create one I rt. clk, saw 3 text document type options, chose "rich text doc" then typed out required user preference lines, saved as .rtf, closed ff reopened, went back to the school forums, tried same editing options but got same response. After exiting completely, reentering my profile the user.js file I thought I made wasn't there. I have scrolled through many many helpful articles, comments etc. here but nothing specific to this file type in profiles? In these instructions, step 3 "open user.js file from that directory in a text editor. If there's no user.js file, create one". That's what I need to do. Then I 'll be ready for step 4 yay! Thanks.

The ff message to me is "to protect users' information, unprivileged scripts cannot invoke the Cut, Copy and Paste commands in the Mozilla rich text editor...to enable these functions you must modify your browser preferences..." This is an online course. In the required discussion forums, and while editing my post for replies- when dragging over a sentence, then rt clk for copy/cut/paste edit options-this is when I get message to follow directions to create a user.js file inside my profiles. I have followed the "Changing the Preferences in Firefox" directions to create a user.js file(did not have one) to add the described and specific capabilities for this site (which is an .edu type site). Since didn't have a "user.js" file to open in a text editor, to create one I rt. clk, saw 3 text document type options, chose "rich text doc" then typed out required user preference lines, saved as .rtf, closed ff reopened, went back to the school forums, tried same editing options but got same response. After exiting completely, reentering my profile the user.js file I thought I made wasn't there. I have scrolled through many many helpful articles, comments etc. here but nothing specific to this file type in profiles? In these instructions, step 3 "open user.js file from that directory in a text editor. If there's no user.js file, create one". That's what I need to do. Then I 'll be ready for step 4 yay! Thanks.

Chosen solution

As soon as you right-click selected text, the site pops up a message about modifying your settings??

On that site, can you use the standard Windows keyboard shortcuts to cut, copy and paste: Ctrl+x, Ctrl+c, Ctrl+v?

If so, I suggest doing that.


Alternately, you can stops sites from replacing the right-click menu by always showing Firefox's menu. This can be a bit inconvenient on some cases, such as Google Maps, where Firefox's menu will hide Google's menu. When that happens, you usually can press the Esc key to remove Firefox's menu and use the site's menu. If you want to change this, here's how:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box above the list, type or paste context and pause while the list is filtered

(3) Double-click the dom.event.contextmenu.enabled preference to switch it from true to false.

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Chosen Solution

As soon as you right-click selected text, the site pops up a message about modifying your settings??

On that site, can you use the standard Windows keyboard shortcuts to cut, copy and paste: Ctrl+x, Ctrl+c, Ctrl+v?

If so, I suggest doing that.


Alternately, you can stops sites from replacing the right-click menu by always showing Firefox's menu. This can be a bit inconvenient on some cases, such as Google Maps, where Firefox's menu will hide Google's menu. When that happens, you usually can press the Esc key to remove Firefox's menu and use the site's menu. If you want to change this, here's how:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box above the list, type or paste context and pause while the list is filtered

(3) Double-click the dom.event.contextmenu.enabled preference to switch it from true to false.

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To return to your question about user.js, the file name needs to be exactly user.js and the file type needs to be plain text. Because Windows hides file extensions by default, it can be difficult to get the file name just right. Please make sure the extensions are not hidden: http://support.microsoft.com/kb/865219.

Once user.js is set up, please note that Firefox only reads the file when it first starts up, so you will need to exit and restart Firefox before your preference takes effect.

That said, because your clipboard may contain data copied from other sites or other programs, it is preferable from a privacy perspective not to open up your clipboard to websites if you can use one of the standard keyboard shortcuts or the context menu.

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Note that the user.js file is read each time you start Firefox and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session and changes made are lost.

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Thank you. Once I got it- those standard hot keys are like the "snip It" tool; that's what I opted for and will keep doing especially with the clipboard vulnerability you've highlighted. And w/ the amt. of responses I'm required to enter and having to redo the user.js so often as you and Cor-el have made clear, simply not worth it. Thank you again SO much!!!~!

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Cor-el Thanks for stating so bluntly- my light bulb's kinda cfl- a little dim at first and more often than I'd like! Theta