This webpage makes my Macbook Air run at full fan speed. (2019 MacBook Air)

[FreeWoRLD83]

It's been a year with my 2019 Macbook Air and I have never heard the fan running loudly as I am a lightweight user. This is the first time I am experiencing such weird case where the cpu starts to climb up in temps and fan follows up running at full speed while I am on this webpage.

I don't see anything unusual with the page so what could be the reason for this? Do you experience the same?

iPhone XS True Tone: how to get rid of the yellow hue

The new iPhones are great but there's something wrong with their True Tone feature — it's a bit too warm, a bit too yellow. But hey, with some tweaking, you can fix this!

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You can see the ramp up halfway into the graphs

 

[xylitol]

Do you experience the same?

Yes, high CPU load in Safari. Adblock Plus or Ka-Block doesn't make a difference (I didn't experiment with other ad or script blockers). No such problem when using Chrome with uBlock Origin.

 

[SmOgER]

MBA 2013. Not quite as drastic temp increase as in your case, actually nowhere near, but it does heat up the CPU.

 

[zzzachi]

i see very high cpu loads in Safari Catalina, too
and the problem is that they stick even if all tabs/windows get closed!

you can see the process by entering "top" in the terminal
com.apple.We 104.4 %CPU, for example.
these are Webworker processes going crazy, while Safari should be idle.

from apple discussions it seems also to occur on Big Sur

I think this is at least a bug in Catalina / Big Sur
if not a security issue with processes still running while they should be cleaned up/removed

here on a mbp 13" 2020, but i guess this also happens on desktops.
but there you probably won't notice because the fans do not spin up that easily

 

[svanstrom]

i see very high cpu loads in Safari Catalina, too
and the problem is that they stick even if all tabs/windows get closed!

you can see the process by entering "top" in the terminal
com.apple.We 104.4 %CPU, for example.
these are Webworker processes going crazy, while Safari should be idle.

from apple discussions it seems also to occur on Big Sur

I think this is at least a bug in Catalina / Big Sur
if not a security issue with processes still running while they should be cleaned up/removed

here on a mbp 13" 2020, but i guess this also happens on desktops.
but there you probably won't notice because the fans do not spin up that easily

I don't see any problems on an up2date MBP16.

CPU Thermal level: 58
GPU Thermal level: 8
IO Thermal level: 8
Fan: 2368.78 rpm
CPU die temperature: 68.38 C
GPU die temperature: 68.00 C

I went there first with javascript off, then on, then loaded the page without any content blockers; only base I didn't cover was accepting the tracking etc.

So if anyone else is dealing with the same problem today it's possible that a third party is loading something; and in the past such networks have even been caught loading bitcoin miners in javascript. 🤷

(If this thread livens up I can always do more to track down the exact cause; but for now I'm like "meh!", because I have an aversion to anything having to do with these user-tracking-evils.)

 

[zzzachi]

it doesnt happen always, but i experience it once in while ... no safari extensions installed

next time your fans spin up high while browsing, close all safari windows, but do not quit.
if they keep spinning, open the terminal and enter "top".
here i see com.apple.We 104.4 %CPU for example and it doesnt go away until i quit Safari

if a bitcoin miner or any web code still lives while no safari window is open,
this is a serious bug and security issue!

 

[svanstrom]

if a bitcoin miner or any web code still lives while no safari window is open,
this is a serious security issue!

Weeeell…

With all the work with service workers and push apis and about a gazillion other things that web-based apps needs to play around with there's actually a lot of work happening in background/windowless uses of web technologies.

I'm not updated on the current state of all that, though; so couldn't even tell you if that tech is mainstream enough for someone to have found a way to sneak a miner into it.

 

[zzzachi]

Activity Viewer.app shows my open macrumors window as
741 https://forums.macrumors.com
but if you show details as "Safari Web Content" (741)

next time it happens i try to nail it down to a website.