Should I ignore the launchSettings.json file from being committed in Git?

launchSettings.json should not be ignored. That repository has since been updated to not ignore it: https://github.com/github/gitignore/pull/2705

Reasons for making this change:

Ignoring launchSettings.json does not make much sense. Now .NET CLI even considers this file when running with dotnet run, as you can read here.

This settings will be useful if shared among project members, so it should be commited to the repo.

Links to documentation supporting these rule changes:

https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-run?tabs=netcore2x

One reason that this might be done as a general practice is to keep secrets out of the repo.

If you're using environment variables to store DB passwords, API keys, and so on, you can configure those for your dev hosting environment under Project Properties -> Debug, as key-value pairs.

That configuration gets persisted locally in the project's launchSettings.json, so by keeping that file out of commits you avoid leaking privileged information into your repo.

Note though, that the current best practice is not to store secrets in this way at all during development, but to use the Secrets Manager instead.

OK now I know why, I deleted that file, but the options of this project are still saved somewhere there, the options simply did not get lost after deleting this file. The file seems to be automatically generated when I do any new change to the project options, so my old version with the new changes is going to be there again.

I am not sure what is the benefit of it in this case, but at least I can say we can probably exclude it from the source control.

Please correct me if I missed anything.

It depends on the context of your project,

If you are going to share your source code with your colleagues or client and wanted to run the project with the same set of settings which you have used apart from default like "uriFormat" which will redirect to a specific Url on application start.

This kind of settings will not be available to next user if it is going to run the code from your repository.