How did you do it? Holding more than one was possible in the old source through storage if I remember right, and we did not delete items when we moved over.
I had one in storage and another in my inventory. I took the one out of my storage and ended up with two in my inventory.
I was also able to hold two "Saddle" (the one you use with a pig) But I think this is due to that quest changing in the new source
Was this an intended feature? I thought it was a glitch since I was able to hold two in one inventory.
You are correct when you say it's a glitch. I believe these problems happen when old- and new source items "meet" So far, however, I have not encountered anything game-breaking with this.