Implement document load cancellation
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Complete remaining algo update_the_image_data
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Track hash changes in session history
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Adds tracking of hash changes in the session history.
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Implement step 5 of select_image_source
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This step is responsible for selecting an image source based on user agent's environment( closest value which is greater than user's pixel density)
In case of no device, maximum density source is selected.
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Implement update source set & select image source
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Make fetch() API use same-origin credentials by default
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Introduce "per task source" cancellation
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Exposing HTMLSourceElement IDL attributes
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