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## Summary of the Pull Request
In tonight's episode of "Can we be even faster?", we will... you know what, just take a look at the code.
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## References
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## PR Checklist
* [ ] Closes #xxx
* [ ] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Requires documentation to be updated
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx
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## Detailed Description of the Pull Request / Additional comments
It is actually a quite common technique seen inside the codebase to first reserve the spaces before pushing something into vectors. I don't know why it is not used here.
Before:
After:
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## Validation Steps Performed
e8a68114e8
