It could be I have misunderstood this entirely. But let us for the sake of sanity clarify something.
Your bones are not moving in edit mode. And the original position is not Pose mode. It is Edit Mode. If you go through and remove all of the contraints you will find the original positions in edit mode, not pose mode.
Are you saying that the bones are actually shifting their original positions that they were in - in Edit Mode?
You are calling Pose Mode the “original position”. This is not the case. This is the modified position. As a very simple example, when you apply a copy location constraint the bone will move in pose mode to that new location if it is different than edit mode. The same is true for all constraints. They modify positions and orientations in Pose Mode. So when you go into Edit Mode the bones will of course “move” to their original location.
This explains this comment:
Must have something to do with drivers, since i noticed it only after i added them to my rig.
Of course, constraints can have an effect of the position rotation (orientation) of the bones while in Pose mode.
My suggestion would be to go back over the entire rig with this simple concept and see which constraint set up is causing the problem and work to correct it in pose mode. When corrected, then you should not see the shift.
Now, unless I missed something entirely even more obvious, this is the root of your problem. And since I was not there watching you build the rig, I can not verify that the positions changed from what you originally set in Edit Mode to another position in Edit Mode. If they did, yes, a bug. But that is not what I am seeing in your description nor the file and it in fact follows the normal laws and workflow of rigging.
Hope this helps you get it sorted.
If in fact, the rigging constraint set up you have is based on sound theory and practice to not normally shift the location of the bone in Pose Mode then, the solution is to submit it as a bug to the bug tracker. Now is the time. Now is when they are working to make corrections.