Several stylings do not load when disconnected from the internet (i.e. behind a corporate firewall)

[giladpn]

ALL software version info

Panel 1.4.5 Panel is loaded with pn.serve from a Uvicorn FastAPI server. Uvicorn 0.30.5 Panel Server on Ubuntu 22.04 Browser is MS Edge on Windows 11

Description of expected behavior and the observed behavior

Please try disconnecting from the internet and connecting (locally) to a Panel server. This simulates the environment behind a corporate firewall, where both the server and the user are in the same network, but no access is available to the web.

Numerous stylings will not work, including:

• button icons from the "tablers" icons
• progress bars as used in the Progress widget
• stylings look a bit different
• Image widgets do not load properly
• adding the Code Editor widget to an app will cause the entire app to break (won't come up)

The screenshots below are informative: they show (in MS Edge) the CDN URLs that are not being loaded. Please note there is more than one. I have not tried out all Panel features, so there may be more.

Extensions loaded

pn.extension('floatpanel', 'tabulator', 'codeeditor',
                     nthreads=n_concurrent_threads)
hv.extension('bokeh')

Screenshots or screencasts of the bug in action