The new header causes high cpu usage

[ApostolosB]

Steps to reproduce

1. Where are you starting? What can you see?
2. What do you click?
3. More steps…

1. The issue started happening when the new header entered beta. If you opted out the cpu usage was normal.
2. Just switch bettween rooms -especially ones that have many users like matrix Hq

From what i read in the element web matrix channel it happens with many browsers and is independent of operating system. Many others faced the issue.

Outcome

What did you expect?

Normal CPU usage

What happened instead?

HIgh CPU usage

Operating system

Linux

Browser information

Firefox

URL for webapp

app.element.io

Application version

.82 stable

Homeserver

No response

Will you send logs?

No

[valynor]

Also on Brave 1.71.114 Chromium: 130.0.6723.58 (Official Build) (arm64) on macOS 15.0.1

Very high CPU use (in Brave Browser Renderer (Helper)) since Element version: 1.11.82, same happened before ~1 month ago when room headers were enabled as beta feature. Switching that off immediately fixed it.

Happens all the time for me when I switch to rooms with a lot of users. esp. noticeable in Matrix HQ. CPU stays high for about a minute. When you switch rooms and switch back later the same happens again.

[mahdi1234]

Similar on desktop, just navigate via keyboard between few rooms quickly and fan kicks in instantly.