# Description

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Please include a summary of the change and which issue is fixed. Please
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List any dependencies that are required for this change.

Implement part of https://github.com/isaac-sim/IsaacLab/issues/1769
(optimization)

This is a breaking change because the fast variant is now enabled by
default.

I also improve sb3 training script, fixed loading of normalization and
fixed the humanoid hyperparameters to be similar to rsl-rl, so we can
compare apples to apples in terms of training speed.

I will probably open another PR for the rest of the proposals.

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## Type of change

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- Bug fix (non-breaking change which fixes an issue)
- Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- This change requires a documentation update

With respect to testing, how do you run a single test?
and is there anything I should add?


## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [x] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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---------
Signed-off-by: Antonin RAFFIN <antonin.raffin@ensta.org>
Signed-off-by: Kelly Guo <kellyguo123@hotmail.com>
Co-authored-by: Kelly Guo <kellyguo123@hotmail.com>