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Preview of Epupp: Live Tamper your Web

Epupp: Live Tamper your Web by PEZ

Tamper with web pages, live and/or with userscripts

5 (1 review)5 (1 review)
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About this extension
Epupp has two modes of operation:
  1. Live REPL connection from your editor to the web page, letting you inspect and modify the page on the fly, with or without the assistance of an AI agent.
  2. Userscripts: Tampermonkey style. Target all websites, or any subset of the web's pages, with prepared scripts that modify or query information from the page. Userscripts can be configured to start before the page loads (document-start), when the DOM is ready but resources are still loading (document-end), or after everything has settled (document-idle).

The two form a powerful pair. The live REPL connection, while happily supporting one-off changes or data extractions, is also a very efficient and fun means to interactively develop userscripts.
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Permissions and data

Required permissions:

  • Extend developer tools to access your data in open tabs
  • Access browser activity during navigation

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
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Version
0.0.7
Size
667.14 KB
Last updated
a day ago (Feb 26, 2026)
Related Categories
  • Web Development
License
MIT License
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