Alert message in MRs “Error occurred while fetching…” appears too often and isn't helpful

The error alert message Error occurred while fetching… or Something went wrong while fetching… appears too often and isn't necessarily helpful. To be honest, it just makes the product feels unstable and buggy.

I couldn't accurately pin down the conditions that trigger this alert. But I noticed that it sometimes appears:

1. If you navigate away from the MR page before it has been fully loaded.
2. When the page has been left idle for a while.
3. There are likely other cases…

Here are some examples:

This is an example from an issue, but I think it also happens in MRs:

Proposal

Improve error handling for polling request errors — the theory being that this is the big majority of cases triggering the error (when user is away from tab, etc.)

• Upon error, silently retry within a few seconds.
• Show the current error only after 2 sequential failures (e.g. reset the counter if there's a success in between)
• Dismiss that error upon the next successful request

Update: any visual tweaks will be handled in a follow-up (to be created).

These visual tweaks may include:

• Text update (e.g. "The periodic update of this merge request is currently paused.")
• Success message (e.g. "This merge request is now updating with live data again")
• Use a GLUI notification component (exclusive with below)
• Use a Toast notification (exclusive with above)