Expected behavior

I expect to have my prompts normally replied to, meaning without any browser freezing.

Actual behavior

No matter what model on Claude I use my browser completely freezes and CPU usage spikes to 100%. This leads to me waiting couple of minutes for browser prompt to force stop page load to appear. Cycle continues on each and every prompt, making Claude.ai completely unusable from Mullvad Browser.

Steps to reproduce

1. Open browser v14.5.7.
2. Go to Claude.ai
3. Enter your prompt

Browser completely freezes (not just one tab).

Issue reproducibility

Always reproducible

When did this start?

After macos 26 update.

Does it work in latest Firefox ESR?

Yes (normal Firefox if that is it)

Browser version

14.5.7

Installation mode

System install (using an installer or a package manager)

Operating system

macOS 26
Macbook Air M1 8GB

Other OS

No response

Profile testing

Issue occurs with a fresh browser profile

VPN Status

Using Mullvad VPN

Additional Information