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"this addon had been removed by its author" https://addons.mozilla.org/firefox/addon/fullscreen-toolbar-hover/

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doesn't the built-in fullscreen mode (F11) do this automatically? what additional benefit did this addon have?

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I want stuff at top of screen to vanish. Unless I hover over it.

It did that before with this add on toolbar autohide 6.7.2

F11 does nothing......

AAAAAAAAAAaaaaaaaagh!

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I want to delete this question

I have got it working again