So you like PDF bookmarks?
And you like to expand and collapse them to your liking?
And you’d also like the PDF file to save and retain this state of bookmarks?!
Hmm… you sound pretty finicky about your settings, just like I am 😀
Every time you open a PDF file, the bookmarks as displayed as set by the author/generating-application. The changes you make, while reading it, do not show up the next time! This is what I do to make the PDF file retain my changes to the bookmarks.
- In Acrobat Professional expand and collapse the bookmarks as you want. This is a change in the PDF, but not yet recorded thus by Acrobat. Hence Acrobat will not prompt you to save it.
- Click File > Save As, and save the PDF as a PDF again. The changes to bookmarks are saved!
- (Optional) Thank the community, for sharing such great tips with us all.
Tip: Keyboard shortcut to quickly collapse all your bookmarks to top-level bookmarks: Select any bookmark and press Shift + / on number pad. Use the forward slash on the number pad.
Update: Embedding my video on the same topic in the post.