[Topic] Keyboard navigation testing

[rianrietveld]

URL: https://wpaccessibility.org/docs/testing/keyboard/
Code: https://github.com/wpaccessibility/wp-a11y-docs/blob/main/docs/testing/keyboard/index.md

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Tasks

This content should be reviewed expanded.
The links need to be checked and updated. The link to https://rianrietveld.com/2016/05/10/keyboard/ should be replaced by content / a page on wpaccessibility.org