I'm using the unofficial SF lookup component on a community page. It shows up and works, but when I click on a value the lookup box disappears. The label stays and the value passed is correct, but the box just disappears. The component is always shown, so I'm not telling it to hide.
If I put a lookup on the page before (to any object), the next page's lookup field works as expected. I also tried just putting any screen before it, but no luck.
It works fine in debug as me or the actual running user (guest).
Old post, but I too was having this issue and was unable to find a solution. So, I started playing around with the options. Once I added an icon, that fixed the problem for me. The format for the icon selection is [standard/custom]:[icon_name]. I entered: standard:account
This shows the standard account object icon and now my Lookup field stays visible after being selected.