Hi @st.brown, please accept my apologies for the inconvenience - I can confirm you found a bug!
One of the limitations of the filter, sort and search functionality you’re using is that some fields are unavailable for filtering and sorting. Here is a conversation about it in the community.
The “link to table” field is, sadly, one of them. What should have happened is that the “Filter” checkbox next to forapptest is disabled, but yours isn’t appearing that way due to a bug.
We are working on a fix for this now, and hopefully it’ll appear on baserow.io soon.
Cheers,
Peter Evans