I second this feature request.
The best way to achieve it is to take Foxit PDF Reader for Windows and reverse engineer it for Linux,
taking care to replicate all of the keyboard shortcuts/accelerator and functionality. And then completing the keyboard accessability that Foxit PDF Reader for Windows left out.
Aside from inserting text and images, the most useful features of Foxit PDF Reader for Windows is the annotations - boxes, lines, typewriter, notes, highlighters - and the bookmarking functions.
Theoretically, Foxit PDF Reader has a Linux community developing a Linux equivalent, but it is a hopeless endeavour. There is virtually no keyboard access, not even for the full range of the most basic navigation of the main pane, and zero keyboard access to the menus. If the user must use the mouse, then frankly, it'll be easier to print the document out, scrawl on it by hand, scan it back onto the server and email it to somebody else.
To circumvent the fatal shortcomings of Foxit PDF Reader for Linux, I have to use two apps: i) Master PDF Editor v4, to create/edit bookmarks; and ii) Okular, to create/edit annotations. Okular saves annotations such that a user of Windows Foxit can see the annotations (and vice versa), but the developers of Okular have decided that the user cannot create bookmarks in the PDF file (in Okular, bookmarks are saved locally on the user's system and thus cannot be shared with another user on another device: crazy!).