PageSigner works with many Chromium-based browsers (e.g. Chromium, Vivaldi, Brave, Google Chrome)

You can load PageSigner from the source files of this repo this way:

1. go to chrome://extensions and Enable "Developer mode"

2. Click "Load unpacked" 

3. Navigate inside pagesigner's top folder and click Open.

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Firefox addon creation is not supported anymore due to missing API in Firefox.