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## Summary of the Pull Request
Fix typos found by codespell. Some of it in documentation and user-visible text, mostly in code comments. While I understand you might not be interested in fixing code comments, one of the reasons being extra noise in git history, kindly note that most spell checking tools do not discriminate between documentation and code comments. So it's easier to fix everything for long maintenance.
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## References
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## PR Checklist
* [ ] Closes #xxx
* [X] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [x] Tests added/passed
* [X] Documentation updated. If checked, please file a pull request on [our docs repo](https://github.com/MicrosoftDocs/terminal) and link it here: [#501](https://github.com/MicrosoftDocs/terminal/pull/501)
* [ ] Schema 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
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## Validation Steps Performed
I have checked and re-checked all changes.
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