Fix: safari bug downloadspeed

[florinm03]

On Safari, the download speed was updating too fast. Moreover, the speed was not readable, and you could see NaN and undefined.

Some pictures before the fix

Same upload on Brave:

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From what I gathered:

• Safari fires progress events very rapidly
• Two events fire within the same millisecond
• Date.now() returns the same value for both, because of 1ms resolution
• elapsed = 0 -> division by zero -> Infinity -> NaN cascade

Brave/Chrome have sub-millisecond timer resolution, so two events within the same millisecond still return different Date.now() values, and elapsed is never 0.

Here is a video of how it looked after the guard.

Screen.Recording.2026-04-26.at.12.16.51.mov

So a "throttle" was necessary, hence the elapsed < 300

Screen.Recording.2026-04-26.at.12.41.16.mov

[Vlad118]

Looks good 😎