Hello.
I don't know if this applies to newest versions or not, but in 1.10.2-2.5.0...
Due to the possibility to convert bags, one can:

1. get a green bag or better;
2. open it;
3. get all items except one, so that the bag doesn't disappear;
4. convert it into 4 bags of lesser tier;
5. do step 3 for these if one wants;
6. convert these back into one;
7. repeat.

Oh. Sorry. Found the issue closed