What steps will reproduce the problem?
(1) Open a PDF with bookmarks, eg. https://hal.inria.fr/inria-00609399v1/document
(2) Click to open the bookmarks dropdown
(3) Press Shift-Tab any number of times

What is the expected result?
The dropdown should be closed.


What happens instead?
The dropdown remains open.



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If this is a regression (i.e., worked before), please consider using
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