Why does the message mention a dev server?

The same watchdog protects development builds, where a reload of the interface is the usual cause. In the installed app, restarting it is the equivalent step.

Is there a playback speed limit?

Replay accepts x1, x2, x5, x10 and x25.

Replay: “The backend stopped responding while loading (no progress for 90s)”

A Replay load reports progress while it downloads. If no progress arrives for 90 seconds, Senzoukria abandons the wait and says the backend stopped responding. Other short messages cover a load already running and a replay that reached its end.

Senzoukria · Troubleshooting · Updated September 2026

At a glance

Watchdog: “The backend stopped responding while loading (no progress for 90s).”
Busy: “a load is already running”
End: “replay finished — seek to an earlier time before playing again”
First load: 30 to 60 seconds for a full session, as the screen notes

What you see

The load gauge stops, then the Replay screen shows “The backend stopped responding while loading (no progress for 90s). If the dev server just reloaded, restart the app and try again.” and returns to the idle state. Two other messages can appear: “a load is already running” when you start a second load, and “replay finished — seek to an earlier time before playing again” when you press Play at the end of a session.

Why it happens

A healthy download reports progress several times per second. Ninety seconds without any is treated as a dead load, so the screen does not wait forever. Causes include a backend busy on a very large day, a network drop in the middle of the history download, or an application that was restarted underneath. Only one Replay load runs at a time; a new load replaces the previous session instead of requiring a manual stop.

How to fix it

Click “Load session” again; a day that was partially downloaded is fetched again.
If it stops again, restart the app and retry.
Reduce “Context history”, since each extra context session lengthens the load by as much.
At the end of a session, seek to an earlier time or pick another day before pressing Play.

What it is not

Not a refused request: refusals come back with codes.
Not lost data: sessions already on disk are unaffected.

When to contact support

If the steps above do not change anything, send the case from Menu → Report a problem, or ask on the Senzoukria Discord. Include the contract, the day, the context history setting and the percentage reached.

In the same section

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Frequently asked questions

Why does the message mention a dev server?: The same watchdog protects development builds, where a reload of the interface is the usual cause. In the installed app, restarting it is the equivalent step.
Is there a playback speed limit?: Replay accepts x1, x2, x5, x10 and x25.

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