Session State Checkbox Bug

Hi, the attached screencasts show a toy app illustrating a bug introduced after V 0.83.0. Ticking and unticking checkboxes in the sidebar results in ghost headers haunting the screen. The ‘ghosts’ are mainly headers in the sidebar but sometimes ghost widgets also haunt the sidebar. The toy app includes a checkbox on the main page. This doesn’t appear to trigger hauntings on the main page or the sidebar.

The github repo with code for the toy app and full details of the environment is . You can investigate different combinations of headers, checkboxes and default values by changing values in the table in parms.xlsx

I have two production apps where this issue is preventing me from upgrading beyond 0.83. It would be great if you could lay the ghosts to rest!