Blink of the room timeline with a blank screen

[giomfo]

Steps to reproduce

User feedback:
"I see this very often in Element-iOS. You click a room in the room list, the timeline appears but only for less then one second maybe, then the content of the tableview is cleared, you see a blank screen in the timeline while the sync badge appears on top. After a short time the timeline will become visible again for the user. Sometimes fast, sometimes it takes a few seconds"

I observed it on my side, this is not systematic. I observed this blank screen most of time when I open a room again after a long time (1 day) whereas only few messages have been added in the room (So this is not due to potential gap during the sync). Push notifications are enabled on my device.

This is easier to reproduce by resuming the app from a push notification (but not systematic). I observed it by selecting the room from the rooms list too.

To illustrate the issue, I recorded 3 different use cases. All of them have been got by resuming the app from the notification panel:

• a blank screen is displayed during the "syncing" whereas the room has been already opened previously in the app, then the timeline is displayed
  
• a blank screen is displayed, then the timeline is displayed briefly (without the 5 most recent messages), then a blank screen, then the room timeline is displayed at the end of syncing
  
• here the behavior is the expected one, no blank screen
  

Outcome

What did you expect?

no blank screen

What happened instead?

sometimes the room timeline disappears several secondes whereas only few new messages have been received

Your phone model

No response

Operating system version

No response

Application version

No response

Homeserver

No response

Will you send logs?

Yes