0.9.15 doesn't render custom index column of dataframe

The community member reported that updating from version 0.9.14 to 0.9.15 breaks the dataframe UI if the dataframe has a custom index column, but the to_markdown() function still works in both versions. Another community member acknowledged the issue and said they can fix it. A pull request was created to address the problem. In the meantime, a community member suggested using '.drop_index' before outputting the dataframe to move the index as a real column. The issue was eventually resolved in version 0.9.16.