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Comment by jsf01 | Hacker News Reader

Cool! Just curious, why do you query 10 times per second for a feed? This seems kind of excessive and maybe a bit bad for battery life, especially since this could be running in several tabs at once.

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This is just the straightforward idea of waiting for some element to appear on the website. But once the element is found, this thing stops. It won't stop for YouTube if you are on Facebook though but it's just a first implementation and it could actually be very easy to recognize the site. Thanks for the helpful suggestion!

I wrote an extension that did something similar for Twitter, back when Twitter had "So-and-so liked this" tweet, which was inevitably something awful. It's archived now, because it's no longer relevant. But you might find something useful in the code.

I tried polling, but it was against the Chrome extension guidelines at the time, so I used a "mutationObserver" on page load and then a "scrollListener". I don't remember if I ever tried an "intersectionObserver" but that might be worth looking at.

https://github.com/rendall/twitter-like-hider/blob/master/co...

hey just curious, can't the mutationobserver catch this instead of that approach?

https://developer.mozilla.org/en-US/docs/Web/API/MutationObs...

Definitely! The current implementation is supposed to just do the work. It's not meant to be optimized or anything.

Added a quick domain check to avoid the issue that you've mentioned :)

I believe you could use a sub tree mutation observer instead of polling.

Yes, definitely use mutation observers. Far faster to react and doesn't require polling, they're better in essentially every way when things aren't changing many times per second.

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