The MY_DATA.HTM page fetches additional information from the website when it is loaded. This is JavaScript to enable functionality on the page, such as the visual preview. If you are working offline, this functionality will not be loaded.

Differences in Online and Offline working

online MY_DATA fileoffline My_DATA file

The offline image shows the file as it is on the micro:bit without the additional styling and images provided by the micro:bit website.