When there is no activity on the page, the system goes into a 'sleep' mode to save resources - as soon as the system detects any kind of movement, the 'Rejoining the server message pops up, and you are reconnected to live IMPOWR. It can occur with any page.
It's more due to browser behaviors than our Blazor server. While a user is on a Blazor page, they have a persistent connection with the server so that they can send data back and forth really fast. But if that connection breaks for whatever reason, they get that "rejoining the server" UI and their page will refresh if it can reconnect. There are really only two reasons why a connection would break:
- The server went down (like during a deployment)
- Your browser tab was put to sleep
Users will almost always see only #2. If you have IMPOWR open in another browser tab, but if they don't visit that tab for a while, their browser will "put the tab to sleep" to save resources, which often means severing the connection to the server since it's not actively being used. Browser sleep behavior, and how much inactivity time it takes before the tab goes to sleep, varies across browsers and operating conditions, so we can't give an exact answer as to how long it takes before users see that message. But thankfully the reconnection experience has really been improved in recent Blazor updates, users should only see that message for a couple seconds before it automatically reconnects them.