I put six idols and one set of unique gloves in my stash then hit logout and went to my second character to use them. Logged over, and they were nowhere to be found. I went back to the original character and double-checked the vendor and while the items I sold hours ago were on the vendor, my new items were not. I checked the stash again with the search feature and all items are still missing.
Used Shift + right-click to place the items into the stash, but the page I was on was full. I just assumed they went to a new page when I logged off and wasn’t aware they completely disappeared until I logged over. Repeated these steps a few times, and the items are indeed gone.