Hack 69. Remove Conflicting Keyboard Shortcuts

Remove annoying access keys from web pages that define conflicting shortcuts.

"Add an Access Bar with Keyboard Shortcuts" [Hack #68] introduced the concept of site-specific keyboard shortcuts (called access keys, after the attribute used to define them). Like Greasemonkey itself, access keys can be used for good or for evil. A malicious web page could redefine all available access keys to point to a link that tries to download a harmful executable or pop up an advertising window. Or a web publisher could with the best of intentions end up defining access keys that conflict with standard keyboard shortcuts in your browser.

Wikipedia, an otherwise excellent online encyclopedia, is such a site. It defines several access keys, including some (such as Alt-E) that conflict with the keyboard shortcuts for opening menus in the Firefox menu bar. This hack removes all access keys from a page to avoid the possibility of such conflicts.

8.4.1. The Code

This user script runs on all pages. It uses an XPath expression to find all the elements with an accesskey attribute, and then removes the attribute. This is enough to get Firefox to remove the associated keyboard shortcut from the link or form field.

Save the following user script as unaccesskey.user.js:

 // ==UserScript== // @name Remove AccessKeys // @namespace http://diveintomark.org/projects/greasemonkey/ // @description remove accesskey shortcuts from web pages // @include * // ==/UserScript== var snapSubmit = document.evaluate("//*[@accesskey]", document, null, XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE, null); for (var i = snapSubmit.snapshotLength - 1; i >= 0; i--) { snapSubmit.snapshotItem(i).removeAttribute('accesskey'); } 

8.4.2. Running the Hack

This hack runs on all platforms, but it is especially useful on Microsoft Windows, where keyboard shortcuts to open menus conflict with keyboard shortcuts defined on the web page itself.

Before installing the user script, go to http://en.wikipedia.org/wiki/Music_of_Mongolia. Press Alt-E to try to open the Edit menu, or Alt-T to open the Tools menu. Holy conflicts, Batman! The web page has redefined Alt-E to jump to the editing page, and Alt-T to jump to the discussion page.

Now, install the user script (Tools Install This User Script), and refresh http://en.wikipedia.org/wiki/Music_of_Mongolia. You can now press Alt-E to open the Edit menu, or Alt-T to open the Tools menu. All the standard key combinations work as you would expect them to.

Wikipedia is the highest-profile site that creates this problem (and it was the inspiration for this hack), but the possibility for conflict exists on any site. I leave this script installed with the default @include *, but if you use site-specific keyboard shortcuts, you can change the @include configuration to target only the sites that cause this problem.