Had this same Issue at the pond just SW of Vybor. Neither me or my buddy could not fill our water bottles in this pond. Could not drink from the pond either.

Have you tried filling the canteen in first person view? This worked for me.

Can confirm first person view worked for me too.

I had better luck using first person with the bottle or canteen in hand and raised, but it can be inconsistent.

The water bottle seems to have more success than the canteen.

I have tried first person, does not work. Although I remember trying it once in a different pond, after going in first person, looking down, then free-looking upwards gave me the option (just once I think)

Seems very inconsistent at this point.

Inconsistent is the word. For example why do you have to be knee deep in a lake for this option to (sometimes) pop up? Why is it not possible to fill a container in a creek?

it is indeed not working as intended, but is very consistent - if you found a position and a camera angle that works, it will always work for any player(as long as you do not move a bit).

if you got solid rocks in the water, go next to them and keep an eye on the context actions - once you got the correct position the drink/refill option will pop up. dont know why the "correct" positions tend to be around rocks, but it eases up refilling quite a lot.

since i am using 3rd person allmost all the time i cannot say if/how that works in 1st, but i guess its similar.

False, it does work perfectly to me.

Works perfectly for me as well. I use 3rd person almost exclusively.

I use 3rd person almost all the time and havn't been able to fill my water bottles or canteens at several different locations. I've tried moving around to find the sweet spot, but it doesn't seem to work at all.

*edit - since this post I tried again. What I didn't realize is that I needed to put my water bottle/canteen onto my action bar and then have the item in my hands. At this point I was able to fill all containers without any issue.

I tried filling my water bottle in a small creek and it was nearly impossible. I tried standing waist deep in the water, searching around for a way to get it but there was only one spot on the body of water where it was possible to do it. It was toward the edge near a rock.

I have found that you must wander in/near the edge of a water source until you find the, "sweet spot." At times this can be very frustrating. Proximity checking for standing water sources should be more forgiving.

Go into first person. It should work.