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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.
As VS 2022 doesn't seem to store files with UTF-8 BOM as often anymore, we've
been getting more and more pull requests which seemingly randomly change files.
This cleans the situation up by removing the BOM from all files that have one.
Additionally, `Host.Tests.Feature.rc` was converted from UTF-16 to UTF-8.
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## Summary of the Pull Request
Many places in this codebase has an equality comparison to the boolean FALSE. This adds unneeded complexity as C and C++ has a NOT operand for use of these in if statements. This makes the code more readable in those areas.
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## References
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## PR Checklist
* [X] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [X] 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
One boolean being compared to FALSE was only used once, with the boolean name being "b", so it is better off not existing at all.
<!-- Describe how you validated the behavior. Add automated tests wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed
Unit Testing passed, compiler refactoring
