DOM inspector

uBlock Origin comes with its own custom DOM inspector, to assist in the creation of cosmetic filters, as a complementary tool to the element picker.

A custom DOM inspector -- rather than creating hooks into the browser's own DOM inspector -- has benefits:

• Portability: does no depend on specific browser API.
• Optimal: the UI is optimized to specifically deal with cosmetic filters.

Whereas the element picker is useful to interactively create cosmetic filters through point-and-click, the DOM inspector is useful to create cosmetic filters through the internal structure of the document in your browser. For instance this allows:

• To create very specific cosmetic filters by selecting an element directly in the DOM hierarchy.
• To create exception cosmetic filters.

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