It is possible but rather difficult. In Netscape this requires UniversalBrowserWrite which can only be accquired with a "Java Permissions" dialog box. I know it's possible in IE as well but I don't know if it prompts you or it it just requires really insecure settings.

Anyways it should be hard, who wants random links to cheese factories, inkjet cartridge resellers and mortgage companies appearing in the bookmarks?

UPDATE: Replaced 'Java Permissions dialog analog' with '"Java Permissions" dialog box'.

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perl -p -e "s/(?:\w);([st])/'\$1/mg"