Steam requires performance observers

[Theresnothinghere]

https://store.steampowered.com/

Steam until now has had pretty good compatibility with Pale Moon as well as performance,
however with a recent update they introduced a new top menu with the search-bar that requires performance observers to be enabled in browsers

Code: Select all

Time: 2025-09-26 13:19:59
Error: ReferenceError: PerformanceObserver is not defined
Source File: https://store.akamai.steamstatic.com/public/javascript/applications/store/main.js?v=xt1Cqyvk_s57&l=polish&_cdn=akamai
line: 13

Maybe it would be possible to define this PerformanceObserver, but make it so that it reports nothing or some default values and include that as a privacy-aware + compatibility option in Pale Moon?

[Moonchild]

Maybe it would be possible to define this PerformanceObserver, but make it so that it reports nothing or some default values and include that as a privacy-aware + compatibility option in Pale Moon?

That's not really feasible. If a site requires performance observers outside of development, then they usually also bind site functionality to them (even though they shouldn't).

If the sites you use need them you can enable them in Preferences (and optionally complain to the webmasters about it).

[Gemmaugr]

Since January, there's been an increasing amount of problems with steam really. First was a broken wishlist (still mostly broken, as one can't change the order around). Then they started advocating for devs to upload AVIF screenshots (which PM doesn't support), and now the Performance Observer thing sadly (and a missing search in the top menu).

I was actually wondering the exact same thing. If spoofing Performance Observer was possible. I'm saddened that it isn't. And there's no way to use it on only one site like a User Agent I guess.. Anyone know more exactly what it tracks? Could it be limited with disabling other About:Config options like observers, events, sensors? and using eMatrix + uBO lists? Ultimately, they shouldn't tie it to site usability indeed, but fat chance we have of changing that alone (I've been in contact with steam support three times for the broken wishlist, but it's just "use chrome/ium").

[sotesz]

I came to find out that even logging in is impossible without this.
The whole form part of the login page doesn't even load without enabling the observers.

If this is something that is better turned off, but some sites simply require it, is there an option to only enable it for specific sites/domains, or even better pages (as currently and seemingly I only need it for the login page)?

Thanks for the thread creator for providing the clue that resulted in a solution for this issue for me!
(And I thought the site got on the right track when the wishlist got partially fixed out of nowhere...)

[Nelraen]

It seems they also need it for video playback, which is annoying. Anyway, thanks for the info, thankfully they do not actively log you out for disabling the observers, at least for now.