context menu toggle to allow ads on a site

Read first: https://github.com/gorhill/uBlock/blob/master/CONTRIBUTING.md
### Describe the issue
### One or more specific URLs where the issue occurs

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### Screenshot in which the issue can be seen

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### Steps for anyone to reproduce the issue
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### Your settings

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- Browser/version:
- uBlock Origin version:
##### Your filter lists

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##### Your custom filters (if any)

Hi I use a screen reader and cant allow ads for a site I want to support such as http://www.phoronix.com/scan.php?page=home

I am using firefox 51 and want to use the applications key to bring up the context menu to allow ads for a site. I cant click in the toolbar as i do not use the mouse thanks