After seeing an idea about having a goto page function I tried again to get bookmarks to work, as a lesser version that with a little forethought could work nearly as well.
On checking the manual it seems that the key combination should be Down + Select - I presume while looking at the place a bookmark should be set. I've tried quite a bit and can't get this key combination to do anything, even when I succeed in pressing both buttons close enough to simultaneously that the original function of both is suppressed.
This behavior has been observed in more than one text file located in /ebk .
I'm running version 47d0537-150518, according to Rockbox Info on my player.
Any suggestions on how to make this work? Or have I instead run into a bug?
Edited to add: I tested a Clip+ with 3.13, and bookmarking works there. No word yet on whether the dev build works on clip+.