Talisman does not give bonus mana generation in river that was posted in 6.1 Notes

(You have to click on the picture to see the stats of the mana regeneration differences.) EDIT: I thought I saw it ij the original notes. However the only proof now is the Talisman on the League Wika

When playing a champion who relies on mana a lot such as Ekko I was trying to gank for my friend in river and I thought to myself after reading the patch note that I can gain the same mana generation in river. I was wrong and it had no effect or any bonus for any regeneration. I was still using my standard regeneration from my basic stats I start with. I tested it out in a custom and you seem to not gain bonus mana regeneration while in river but in the actual jungle except river. I saw the buff in the notes during 6.1 but was it removed or is it bugged?