Greasemonkey compatible script manager for Chrome.
Violentmonkey, UserScript support for Opera, just like Greasemonkey for Firefox and Tampermonkey for Chrome.
Create and manage add-ons made from Greasemonkey and Scriptish user scripts
Reuse data from one website on another. Try Site Connector, a fast and convenient productivity boosting extension.
Yet another Greasemonkey available as Chome and Safari extension.
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