4k-js has low framerates and high performance impact

[muzikbike]

Summary

Notch's JavaScript implementation of Minecraft 4k is quite jittery in Ladybird and consumes quite a bit more memory than in other browsers, resulting in a noticeable CPU temperature increase.

Operating system

Linux

Steps to reproduce

1. ./Meta/ladybird.py run ladybird https://theintraclinic.com/archive/minecraft4k-js/
2. Observe
3. Compare this webpage to how it runs in other browsers

Expected behavior

It would be smooth like in other browsers.

Actual behavior

It is not.

URL for a reduced test case

https://theintraclinic.com/archive/minecraft4k-js/

HTML/SVG/etc. source for a reduced test case

N/A

Log output and (if possible) backtrace

ninja: Entering directory `/home/conputer/other-dev/ladybird/20250807210822/ladybird/Build/release'
[0/2877] cd /home/conputer/other-dev/ladybird/2025080721.../cargo/build --release -- -Cdefault-linker-libraries=yes
    Finished `release` profile [optimized] target(s) in 0.11s
[1/2877] cd /home/conputer/other-dev/ladybird/2025080721.../cargo/build --release -- -Cdefault-linker-libraries=yes
    Finished `release` profile [optimized] target(s) in 0.03s
[4/15] Running utility command for _cargo-build_libjs_rust
2471.619 WebContent(11174): Unhandled JavaScript exception: [TypeError] Cannot access property "getContext" on null object
2471.619 WebContent(11174):     at init (https://theintraclinic.com/archive/minecraft4k-js/js/chambered.js:75:53)
    at https://theintraclinic.com/archive/minecraft4k-js/js/chambered.js:210:5

Screenshots or screen recordings

No response

Build flags or config settings

No response

Contribute a patch?

• I’ll contribute a patch for this myself.