401 after idle app in browser with OAuth2 proxy

[anders-kiaer]

How to reproduce
Steps to reproduce the behavior:

1. Open a deployed app in browser. The app should be behind an OAuth2 proxy doing auth.
2. Let it be idle for some time (might be order of ~1 h, not tested exactly).
3. Do e.g. some button clicking that would trigger callbacks in the Dash app.
4. Observe in browser console that requests get 401 response.
5. The 401 is gone if Dash app page is reloaded in browser.

Expected behavior
Not having to reload for callbacks to work without 401.

Screenshots