Kobo Glo firmware 3.1.1 et al.
Already in 3.1.0 my Pocket account was suddenly gone. A friendly post in a similar thread helped me to get it back. Simply edit the file .kobo/affiliate.conf and instead of Rakuten, but KoboIndigo. Rebooting and the Pocket account was back under Settings -> accounts.
Kobo patcher (libnickel)
For the Kobo patcher (see here and here for description) that patches libnickel, the latest released version of the patcher at the moment is mz_koboreaderpatch_11.zip, see this post in the Russian forum thread.
All that I said concerning 3.1.0 holds the same way. With help of the usual Kobo Patcher thread we could collect the important data. The default values (not what I used, I didn’t patch till now) are found in the config file (mind that the footer is adapted differently then other suggestions): kpg-3.1.1.conf (needs to be renamed to kpg.conf before running the patcher).