'That container cannot hold any more items' error with chests

Oftentimes I'll be looting a chest, and I'll use Strength so I can carry a little bit more with me back to town, and even though I have the necessary capacity (post-strength) to carry certain things it says I can't carry more items. Usually I'll be able to get to say 421/428 capacity but if I try to load a few more gems it'll say I cannot do so, even though said gems would not put me over 428.

you can only have up to 125 items in a container (including your backpack). even though you're not over-weight, you may be hitting the item max

Didn't know that. I'll double check next time, but I'd be surprised if that was the case unless stacks of gems count as more than one item?

nope, a stack of gems will count as one. however if you have 20 items inside a pouch or chest, it counts as 21 items in your inventory (20 + 1 for the container).

hope you're able to figure it out!