@baskerville:
Given that the default exclude list has a bunch of .kobo in there, I'm going to assume yes ^^.
(Much more importantly than Dropbox, books bought from Kobo are in there, you definitely wouldn't want to exclude those ;p).
Code:
\.add
(\.kobo|koboExtStorage)/articles
(\.kobo|koboExtStorage)/images
(\.kobo|koboExtStorage)/kepub
(\.kobo|koboExtStorage)/screensaver
(\.kobo|koboExtStorage)/slideshow
(\.kobo|koboExtStorage)/dict
(\.kobo|koboExtStorage)/certificates
(\.kobo|koboExtStorage)/webcache
(\.kobo|koboExtStorage)/webstorage
(\.kobo|koboExtStorage)/sunpinyin
\.fseventsd
\.Spotlight-V100
\.Trash
\.Trashes
\.Trash-\d+
\$RECYCLE.BIN
Inserted into
Code:
^/mnt/(sd|onboard)/%1$
Which means we can't use ^ or $ in the setting's pattern.
----
IIRC, the issue is that the setting *overrides* the default list, which explains the strictness.
If you have a pattern on hand that does both, I don't have any qualms about replacing it, but, this one works for 99% of use-cases and hasn't eaten anyone's data so far

.